Streamed live October 15, 2024. Let's look over the long life of the  Neil Gehrels Swift Telescope as it watches for the multi-spectral flashes of high energy explosions.

Streamed live on Sep 30, 2024. Let's talk about that giant telescope that's changing everything. We have been waiting our entire careers to make this episode on the James Webb Space Telescope, AKA the JWST. This historic Observatory was launched just a couple of years ago and it's already overturning our understanding of the early Universe star formation and exoplanets!

Streamed live on Sep 23, 2024. Last week, we talked about the Parker Solar Probe. As always, we like to talk about the person who inspired the mission. What makes this amazing and different is that Eugene Parker was there to watch the launch of the mission that shares his name. Why is he so influential on solar astronomy?

Streamed live on Sep 16, 2024. Let's look over the long life of the Parker Solar Probe as it explores the Sun and nearby worlds. The Sun! It’s that ongoing thermonuclear explosion that’s happening right over there! And although the Sun is necessary for life on Earth, we still have questions! So NASA has sent the Parker Solar Probe to visit the Sun up close, to get us some answers.

Streamed live Sep 9, 2024. We made all sorts of predictions, and some of the stuff we didn't know about last July, somehow, we still don't know about as we set up this episode on September 3! Join us for the first episode of Season 18 as we review all the crazy space science that happened during our Summer Hiatus. 

Streamed live on Jun 24, 2024. Normally Pamela refuses to think about the future. But today, on our final episode before hiatus, she’s throwing out those rules. It’s like the PURGE! Here’s what we’re excited about for the future. Especially for the next couple of months until we return in September.

Streamed live Jun 20, 2024. Fraser & Pamela list their favorite books! Take notes! I also have a favor to ask - I'm working on a research project with my collaborator Sanlyn Buxener on what factors help and hinder people learning and doing science. Can you please take our survey? bit.ly/AstEco THANK YOU! - Pamela

Streamed live on Jun 10, 2024. Astronomers have discovered thousands of exoplanets, revealing entirely new types of worlds that we just don’t have in the solar system. It’s enough to start getting a rough sense of what kinds of planets are out there. What’s the big picture?

Here’s a familiar question: How’s the weather? We’re familiar with the weather on Earth and telescopes and missions are watching the weather on other planets in the Solar System. But for the first time in history, astronomers can now answer that question for exoplanets, located light-years away from us.

Most of the exoplanets we’ve found are around stars, where they belong. But a few have been found free-floating in interstellar space. The evidence is growing that there are a lot of them out there, maybe even more than planets with stars. How do they form and how can we learn more about them?

Streamed live on Apr 30, 2024. Our galaxy series continues with elliptical galaxies. Unlike other types, these are large, smooth with very few distinguishing features. They’re filled with red and dead stars, a clue to their evolution.

Our galaxy series continues, on to spiral galaxies. In fact, you’re living in one right now, but telescopes show us the various shapes and sizes these galaxies come in. Thanks to JWST, we’re learning how these spirals got big, early on in the Universe.

Streamed live on Apr 30, 2024. It’s time to begin a new mini-series, where we’ll look at different classes of galaxies. Today, we’ll start with the dwarf galaxies, which flock around larger galaxies like the Milky Way. Are they the building blocks for modern structures?

How old is that star? That planet? That nebula? Figuring out the ages of astronomical objects is surprisingly challenging. Fortunately, astronomers have developed a series of techniques they can use to work out the ages of stuff.

Last week, we learned about the death of Peter Higgs, a physicist and discoverer of the particle that bears his name. The Large Hadron Collider was built to find and describe the particle. Today, we’ll look back at the life of Peter Higgs and his particle.

How to watch a solar eclipse and do some science! The next great eclipse is upon us, with viewers across North America witnessing the moon passing in front of the Sun. It’s an amazing experience, but also an opportunity to do science. Let’s talk about what we can learn from this momentous event.

Several of the planets and moons in the Solar System are in orbital resonance, orbiting in a geometric lockstep. And not just the Solar System, astronomers have found the same resonances in other star systems.

Last week was one of the most exciting meetings we’ve seen from the Lunar and Planetary Science Conference, with hundreds of announcements and discoveries from various missions. One theme kept coming up, the Solar System is more volcanically active than we thought. Today, we’ll explore volcanism on other worlds.

You’ve probably heard that the best kind of science is peer-reviewed research published in a prestigious journal. But peer review has problems of its own. We’ll talk about that today.

NASA works on many missions using tried and true technology, but they also invest in creative ideas that could drive the future of space exploration. It’s called NASA’s Innovative Advanced Concepts or NIAC.

In the olden days, NASA developed its missions using a variety of in-house engineers and external suppliers. As more commercial companies are targeting the Moon, NASA is working with partners to deliver its payloads to the lunar surface. Today let’s talk about NASA’s Commercial Lunar Payload Program.

Streamed live on Feb 19, 2024. [My apologies for Fraser’s audio dropouts. We’re not sure how it happened as it wasn’t happening at his studio. Audio is a black art, IMHO. Rich) Last week we learned that Russia might be planning nuclear weapons to take out satellites in space. What is the current and future possibility of weapons in space and what are the treaties designed to prevent them?

Last week we talked about sample return missions from the Moon and Mars, but scientists have retrieved samples from other objects in the Solar System, including comets and asteroids. What does it take to return a piece of rock from space, and what have we learned so far?

We’ve sent robots to other worlds, but the amount of science we can deploy to another planet can’t compare with the vast science labs we have on Earth. That’s why more and more missions are for a sample return, bringing pieces of alien worlds back to Earth, where we study them with proper equipment.

We’re so familiar with NASA’s exploration efforts in space, but you might be surprised to learn that China launches almost as many rockets as the US. They’ve got their own space exploration program that could soon bring humans to the surface of the Moon. Let’s give a brief overview of China’s space exploration plans.

Wherever we find liquid water on Earth, we find life, so it makes sense to search for water across the Universe, and hopefully we can find evidence of life. But what about worlds which are completely covered in water, oceans hundreds of kilometers deep. Can there be too much water?

NASA’s Juno spacecraft has completed dozens of flybys of Jupiter, seeing the planet from many angles and delivering some of the most beautiful images we’ve ever seen of the Jovian world. Now it’s focusing in on Io, sending home images of the tiny volcanic world from just 1,500 km away. And the best is yet to come.

Streamed live on Dec 20, 2023. Solar cycle 25 is shaping up to be a doozy, with plenty of flares and coronal mass ejections blasting off the Sun. As the solar activity continues to rise, how are things shaping up?

Streamed live on Dec 11, 2023. With Artemis 1 completing its robotic flight around the Moon, we know that the SLS works. Next comes Artemis 2, with a crew of astronauts flying past the Moon. If that’s successful, we could see humans set foot on the Moon in December 2025. But there is a long list of challenges to consider that could delay things considerably. Go or no go for launch‽

Last week we looked back at some of the ideas that science has changed its mind about. This week we look forward, into the future, at some of the big ideas that astronomers are making progress in. What space science are we looking forward to?

Astronomers talk about all the amazing discoveries they’re making but sometimes, it turns out, they were wrong. After decades and centuries of discoveries, how have they changed their minds?

Just a warning, the holidays are rapidly approaching. It’s time, once again, to think about what to buy all the space nerds on your lists. Here’s what we like.

How the time flies. It’s been over a year since JWST went operational, with other missions joining the fun. What new insights have we gained about the Universe thanks to these powerful new tools?

Finally, we reach the end of our tour through the missions in the Solar System. Out beyond Mars, to Jupiter, the Kuiper Belt and Beyond.

Another week, another review of space missions in the Solar System. Today we set our sights on the red planet. What are all the active missions at Mars today?

Our journey through missions continues, this time we focus on the Moon. There are many nations on the Moon, near the Moon, around the Moon, traveling to the Moon. It’s a lot. We’ll talk about it today.

Our journey through space missions continues. Now we move away from the Earth to the rest of the solar system. What’s out there orbiting, roving and flying on other worlds and in interplanetary space. Today we look inward and we’ll talk about the missions studying the Sun, Mercury and Venus.

Last week, we brought you up to speed on the spacecraft which are helping to study Earth from above. Many of our missions are in Earth orbit but looking outward to study the Universe. Today, we’ll talk about the missions close to home, helping us understand our place in the cosmos.

It’s time for another series! This time we’re gonna look at the missions that’re currently in place across the solar system. Today we’ll start with the key missions here on Earth, studying the planet from above and looking out into the Universe. 

Jupiter’s Great Red Spot is one of its most iconic features. First seen hundreds of years ago. Although it’s certainly long lasting, it’s been changing in size over the last few decades. Shrinking, changing in color. Is it fading away? And what can the changes tell us about storms on giant planets?

Streamed live on Sep 18, 2023. We’ve looked at Earth’s changing climate, now let’s see what it’s like for another world: Mars. Much looks familiar, but some of it is totally alien, from ice caps of frozen carbon dioxide to planetary dust storms that can obscure the entire world from view.   This video was made possible by the following Patreon members: Stephen Veit Jordan Young Jeanette Wink Andrew Poelstra Brian Cagle David Truog BogieNet Gerhard Schwarzer David THANK YOU! - Fraser and Dr. Pamela

Streamed live on Sep 11, 2023. It’s official! June and July were the warmest we’ve seen since records began over a century ago. Fires are rampant across Canada, and we’re seeing record droughts around the world. Today we’re going to look at 20 years of climate science, how well does reality match up with the predictions.   This video was made possible by the following Patreon members: Stephen Veit Jordan Young Jeanette Wink Andrew Poelstra Brian Cagle David Truog BogieNet Gerhard Schwarzer David THANK YOU! - Fraser and Dr. Pamela

Hiatus Message Once again, we’ve reached the end of a season here on Astronomy Cast, and it’s time for the summer hiatus. See you in September!

Streamed live on Jun 26, 2023. Once again, we’ve reached the end of a season here on Astronomy Cast, and it’s time for the summer hiatus. But the Universe never takes a break. What can we expect to happen over the summer while we’re catching up on our reading, building our gardens and planning for Season 17?

We’re going back to the Moon. In the next few years humans will set foot on the Moon again, ideally this time to stay. But this will be different than the Apollo era, going to the scientifically fascinating, and difficult southern pole of the Moon. What needs to be done to prepare the way back to the Moon?

The permanently shadowed craters on the Moon are the focus of so much research. That’s because they seem to contain vast reserves of water ice. Water we could use for oxygen, propellant and so much more, but also, to help us understand where the Earth’s water came from.

Launching satellites from Earth is counter-productive. You’ve got to make a satellite that can handle Earth gravity, then the brutal flight to space, then deployment in orbit. What if you could build your spacecraft in space?

One of JWST’s top jobs is to peer deeper into the Universe than ever before, watching as the first galaxies came together. Surprisingly, astronomers found galaxies that seemed much more mature than expected, much earlier than it was believed possible. What’s going on and what does it mean for cosmology?

After the cosmic microwave background radiation was released, the Universe returned to darkness, cloaked in this clouds of primordial hydrogen and helium. Gravity pulled these vast clouds into the first stars, and then the first galaxies. This is Cosmic Dawn, and JWST will help us probe this mysterious time in the Universe.

Astronomers first noticed the strange behaviors of rotating galaxies almost 100 years ago, suggesting there’s an invisible dark matter hold them together with gravity. Or maybe we just don’t understand how gravity works at the largest scales. Observations are much better now, and astronomers have found examples of galaxies that are almost entirely made of dark matter. Does this tell us anything?

In 2017, astronomers detected the gravitational waves and electromagnetic radiation from colliding neutron stars. This had been long theorized as one of the causes of a certain type of gamma-ray burst. By studying the event and its afterglow, astronomers have learned a tremendous amount about the formation of the heaviest elements in the Universe.

Last week we talked about rogue stars. This week we’re going to take things up a notch and talk about an even more extreme event. Rogue black holes. Astronomers recently discovered a supermassive black hole on an escape trajectory, leaving newly forming stars in its wake. It’s wonderful, terrible, nightmare fuel.

Most stars in the Milky Way are trapped in here with us, doomed to orbit around and around and around. But a few have found a way out, an escape into the freedom of intergalactic space. How do stars reach escape velocity, never to return?

Okay sci-fi writers, today we’re going to give you a guided tour of building planets. How they form, how they grow, and how things can go horribly horribly wrong. [Editor’s Note: Google HL Tau, click on the Wikipedia link and see planets forming!]

Whenever astronomers discover something surprising, the answer often turns out to be dust. Dust obscuring our view, dust changing the polarity, dust warming things up, dust cooling things down. It’s always dust. Until it isn’t.

We’ve spent a lot of time gushing about Saturn’s rings, but there are other places with ring systems. And not just Jupiter and the ice giants, but asteroids, dwarf planets, centaurs and even exoplanets. Today let’s gush about them!

Ice is ice, right? You know, what you get when water freezes. Well, maybe here on Earth. But across the Universe, water can be squeezed together at different temperatures and pressures, leading to very different structures. Today we’ll talk about the different forms that ice can take.

The asteroid apocalypse is one of those existential crises that keep astronomers up at night. But the DART mission showed us that we can push an asteroid off its trajectory if we have enough warning. Today we’ll talk about how humanity is building early warning systems to give us time to respond to a dangerous asteroid.

If you’re in dark skies and look up, you’re certain to see a satellite. Lots of them. But how can you know which one you’re seeing, and how can you improve your chances of a sighting? Today we’ll talk about how to see satellites, or avoid seeing them.

We’ve talked about the rising problem of space junk. Okay, we know it’s an issue. So what can be done about it? Today we’ll talk about ideas to remove space junk, making sure space is open to use for the centuries to come.

Last week we talked about the laws that govern space exploration. This week the rubber hits the road. What are the consequences for actually breaking these rules? Are they really going to stop anyone?

Streamed live on Feb 13, 2023. The Universe was inaccessible for most of human history, but the first tentative steps to space in the 20th Century made humanity realize that science fiction was becoming science reality. New rules would have to be written to govern how we used this limitless expanse. Today we’ll talk about the Outer Space Treaty of 1967.

It’s been over 20 years since astronomers first discovered that the expansion of the Universe is accelerating thanks to dark energy. And in these decades, astronomers still don’t have much evidence for what could be causing the increased expansion rate. Maybe there’s something else going on to explain it.

Astronomers have made extremely accurate measurements of the expansion rate of the Universe and come up with different results. And the error bars for the observations don’t overlap, so there’s something strange going on. What’s the answer and how can the Crisis in Cosmology be resolved?

Astronomers came together in January to present their newest research. And not surprisingly, the winter AAS meeting was heavy on news from the James Webb Space Telescope. What were some of the new results that were announced?

Well, we did it. We made it to episode 666, an auspicious number to be sure. What can we do to celebrate this accomplishment? An episode all about things in the Universe that have been named after mythological people and places in the underworld!

The Cosmic Microwave Background Radiation tells us so much about the Universe. After that era, the Universe went dark. Then, as gas pulled together into the first stars and eventually galaxies, light returned, beginning the Age of Reionization.

The Sun is a third-generation star, polluted with metals from long-dead suns. Astronomers have also discovered second-generation stars, with very low metallicity. But theories suggest there must be a first generation, with stars made from only pure hydrogen and helium. Can we ever find them?

We generally save our stargazing suggestions for the summer, when it’s warmer in the northern hemisphere. But you’re tough, you can handle a little cold. And it’s worth it because there are some wonderful things you can see in the night sky this time of year.

Last week we talked about the missions we’re saying goodbye to. This week, we’re going to talk about some upcoming missions to say hello to. Some are brand new ideas, others are, uh, recycled.

It’s always sad to say goodbye, but when we send our robotic emissaries out into the cosmos, it’s just a matter of time before they shut down. Today we’re going to say goodbye to a few missions which have reached the end of their lives… But they were very good robots.

Moons orbit planets, planets orbit stars, stars orbit within galaxies. It’s orbits all the way down. But occasionally objects can receive a powerful kick that sends them on a journey, never to return.

Streamed live on Nov 8, 2022. Light pollution is big problem and it’s only getting worse. Not just near cities, but everywhere thanks to increased satellite constellations. How bad is the problem, and how can we fix it?

Streamed live on Oct 31, 2022. We’re recording this episode on Halloween, so how could we resist but take advantage of this opportunity. Space is already terrifying enough, you know, with the vast endless emptiness, the incomprehensible mysteries, and the uncaring coldness. But here are some scary stories to spook it up a notch.

Space is a big place, with lots of galaxies, stars, planets, moons, and that means a lot of names. So how do astronomers name stuff, like comets, asteroids, exoplanets, craters?

Streamed live Oct 3rd. This week we saw the incredible image of DART smashing into asteroid Dimorphous. Beyond avenging the dinosaurs, what can we learn scientifically from this and other asteroid/comet impact missions

Streamed live on Sep 26, 2022. It’s been about 65 years since the Soviets launched the first orbital satellite into low Earth orbit: Sputnik 1. Now there are thousands of satellites in orbit, with tens of thousands on the way. Let’s look at the impact that Sputnik had on the history of spaceflight.

To battle climate change, we’ll need to rapidly move to carbon-free sources of energy. But this technology isn’t a free lunch. They require metals, generate waste and deplete the environment. What’s the best way to balance this shift?

Climate change is on our mind these days with increasing wildfires, droughts and floods. What are the variables that play into a planet’s changing climate and what can this teach us about the search for habitable planets in the solar system and across the Milky Way?

Last week we talked about how single-use rocketry has changed over time, and the role it still plays in launching payloads into orbit and beyond. Today we’ll address the stainless steel elephant in the room and talk about the shift to reusability.

Season 16 opener. On the day that we’re recording this, NASA’s Space Launch System is about to blast off. But everyone is expecting it’ll be delayed to October. When it does launch, it’ll be the most powerful rocket on Earth. Well, until Starship blasts off. So are we about to see the end of single-use rockets and enter the era of reusable rocketry?

Well, this is it. We’re FINALLY going to talk about the James Webb Space Telescope. After decades of development, delays, budget creep, the powerful infrared observatory is at its final home at the L2 Lagrange point. Yesterday (at the time we’re recording this) we saw the first scientific images from the telescope and according to Pamela’s rules, we’re finally allowed to talk about it.

Well, this is it. We’re FINALLY going to talk about the James Webb Space Telescope. After decades of development, delays, budget creep, the powerful infrared observatory is at its final home at the L2 Lagrange point. Yesterday (at the time we’re recording this) we saw the first scientific images from the telescope and according to Pamela’s rules, we’re finally allowed to talk about it.

Well, this is it. We’re FINALLY going to talk about the James Webb Space Telescope. After decades of development, delays, budget creep, the powerful infrared observatory is at its final home at the L2 Lagrange point. Yesterday (at the time we’re recording this) we saw the first scientific images from the telescope and according to Pamela’s rules, we’re finally allowed to talk about it.

Have you ever noticed that significant space and astronomy events seem to happen during the holidays? It’s not a coincidence. There’s actually a reason why. Today we’ll talk about some of the key events that happened during holidays and the underlying rationale.

Summer is officially, astronomically here, and for the folks in the northern hemisphere that means it’s a perfect time to head outside and see what’s happening in the sky. Today we’ll give you a good list of things to keep an eye out for with or without a telescope.

[Editor's Note: The Q&A section was lost when the internet & software demons did their thing. Sorry. I did get the initial co-host banter part adequately. -- Rich] Summer’s here! And that means finally tackling that huge list of books piled up on your bedside table and filling up your Kindle. What books do we recommend for some fun reads this summer?   - The Kaiju Preservation Society by John Scsalzi - Space Opera by Katherine Valente - The Culture series by Iain M. Banks (The Player of Games) - Six Wakes by Mur Lafferty - Marco and the Red Granny by Mur Lafferty - Reamde and The Fall by Neil Stephenson - Bobiverse series by Dennis E. Taylor - Project Hail Mary by Andy Weir - Childhood’s End by Arthur C. Clark - Lagoon by Nnedi Okorafor - Packing for Mars by Mary Roach - The Mission: A True Story by David Brown - Galaxy: The Prettiest Star by Jadzia Axelrod

We always say that we're living in golden age of space and astronomy, but it feels like things are just accelerating. Space travel is happening! What does the long-term future hold for our place in the Universe?

The International Space Station has been continuously inhabited for over 20 years now, serving as a peaceful collaboration between space-faring nations. But it's a machine, and it's getting old. In addition, the Russian invasion of Ukraine has made things, complicated. What's the future for the ISS?

We've now discovered thousands of exoplanets, we're learning more and more about the kinds of planetary systems there are out there across the Universe. But are planets like Earth unique or totally rare?

All the waiting is over, we've finally seen the image of the event horizon from the supermassive black hole at the heart of the Milky Way. Different shaped blobs! And a black circle in the middle. What are we looking at? Today we're going to explain the picture, and what's next for the Event Horizon Telescope.

We've always assumed that we lived in a perfectly normal star system with a normal star and normal planets. It's all... normal. But with our modern understanding of billions of stars, just how normal is our Sun, anyway?

The Earth is teeming with life, but the upper atmosphere to kilometers underground. There's no question that our planet has life. But is our planet itself alive? This is a question posed back in the 1970s as the Gaia hypothesis, and it got its share of criticism. Some new ideas have been proposed to bring this hypothesis to the modern era as we search for exoplanets.

There are general-purpose telescopes and missions that astronomers can use to study specific objects. And there are the survey missions that look at the entire sky, which astronomers can use to answer questions about the Universe. We've talked about surveys in the past, but the landscape is changing quickly so it's time for an update.

Knowledge moves forward, and so, we must move with it. Today we'll give you an update on some of the most fascinating, fast-changing topics in astronomy, astrophysics and cosmology.

Although humans have never actually been to Mars, explorers have simulated many aspects of Mars missions here on Earth. There are missions under the ocean, on the tops of volcanoes, in the harsh Canadian north, and even in bed that simulate the limitations of spaceflight, and teach us many of the lessons to prepare us for the real thing

Computers are a big part of astronomy, but mostly they've been relegated to doing calculations. But recent developments in machine learning have changed everything, giving computers the ability to do jobs that humans could only do in the past.

We think of space as a vacuum, but there are regions of different density. There are winds blowing from stars and other objects that clear out vast bubbles in space, and look absolutely fantastic in pictures. And they might have been critical for Earth to even exist in the first place.

As astronomers look out across the Universe. They see various objects spewing jets of material light years into space. What causes these jets? And what impact do they have on the Universe?

The Milky Way is a vast grand spiral today, but how did it get this way? Astronomers are starting to unravel the history of our galaxy, revealing the ancient collisions with dwarf galaxies, and how they came together to build the modern Milky Way.

We've always assumed that habitable planets would need to be like Earth; a terrestrial planet orbiting a sunlike star. But now astronomers have been discovering planets in the habitable zone around very much non-sunlike stars. What strange places could be habitable?

A recent image from the South African MeerKAT Telescope blew our minds. It was a high resolution image of the center of the Milky Way showing delicate filaments and other structures. What was so mind blowing is that this was an image from a radio telescope. Today we’re gonna talk about why this was such an accomplishment and what the future holds for radio astronomy. https://www.sarao.ac.za/media-releases/new-meerkat-radio-image-reveals-complex-heart-of-the-milky-way/

Pulsars are the rapidly spinning degenerate husks of dead stars, turning hundreds of times a second. But they're also handy clocks, spinning with such certainty and accuracy that astronomers can use them for all kinds of stuff. We might even use them to navigate the cosmos.

In a rare moment of weakness, Pamela has decided she's open to the possibility that a future exists. That missions, telescopes and spacecraft are going to be built and they're going to do science. Today we'll talk about what we're looking forward to before she changes her mind and my naive optimism for the future.

With all the success of James Webb so far, it's looking like science's huge gamble is going to pay off, but there were years of delays and budget overruns. What impacts did these delays have on science, careers, and the future of space exploration?

Once again, it's time to take a look at the Sun. You know, the ongoing thermonuclear explosion of fusing hydrogen that's right over there. Fortunately, there's a fleet of spacecraft and ground observatories ready to give our best ever view of the Sun, so we can watch it. Always watching…

It’s been about a thousand years since since we last looked at Mercury. So we figured it’s time for an update. What new things have we learned about Mercury? Or even new questions! Fortunately there’s a mission on the way to help us get some answers.

We continue our refreshed tour of the solar system, checking in on the inner terrestrial planets, Mercury, Venus, Earth and Mars. What have we learned about the formation, evolution and what they might tell us about planets across the Universe.

We've reached the end of 2021 and this is the last episode of the year. Let's look back at the big space events of the last year and talk about what we're looking forward to in 2022.

We've talked about the icy objects of the Solar System, today let's talk about space rocks. There's a surprising variety of rocky material in the Solar System, and each object has a story to tell about the history and formation of the planets, moons and other rocky bodies.

Are asteroids dangerous? Well, just ask the dinosaurs and they’ll tell you a sad story of fiery death. It turns out we’re in a shooting gallery of space rock and metal. And somewhere out there there’s one with our name on it. Should we be worried? Or are the risks so minimal to be irrelevant.

So a rock is a rock is a rock. Right? Across the solar system there are giant rocky asteroids and even “gianter” rocky moons. What is the difference between these two families of objects and where do they come from?

For the longest time the only gas giant planets that we knew about were Jupiter and Saturn. But now, in the age of extrasolar planets, astronomers have discovered thousands of gas giants across almost as many star systems. What new discoveries have been made about gas giants, both here in the solar system and across the Milky Way?

Good News! Over the next few years we’re gonna see a flotilla of new missions headed to Jupiter and Saturn. Why aren’t we seeing more missions to the outer planets like Uranus and Neptune, even Pluto? It turns out those places are far away. Today let’s talk about the challenges of exploring the outer, outer solar system.

The outer Solar System is far enough from the Sun that water doesn't get blasted away into deep space. In this icy realm, there are many worlds with vast quantities of water ice. Today let's look at the icy outer moons and dwarf planets.

So we’re learning more & more about the outer planets of the solar system. Uranus & Neptune are Ice Giants, filled with water and other volatiles that we'd consider ice if it was here on Earth. What’s inside these worlds and what can we expect to find across the Milky Way as we find more?

Funding for basic science has always been tricky business, coming mainly from universities, government, companies or wealthy individuals. But who knows how many fascinating discoveries were never made because of a lack of funding. And we now live in an era where regular people can come together to fund scientific discoveries.

Well, you’re familiar with the Hubble Space Telescope of course, but it’s just one of NASA’s Great Observatories. After Hubble came 3 more incredible telescopes. Each greater than the last! (That’s not true… The first one was the greatest.) But together they would fill in almost the entire electromagnetic spectrum.

After Pluto lost its planethood we were down to 8 planets. But there’s growing evidence of another world or worlds out beyond the orbit of Pluto. Is Planet 9 out there and how will we find it? Could there even be a Planet 10?

So there are asteroids, and there are comets. But there’s an entirely separate class of objects called centaurs. But instead of half human, half horse, imagine an object that’s half comet, half asteroid, but 100% interesting!

It's been 15 years since Pluto was kicked out of the planet club. It also happens to be the topic of our very first episode of Astronomy Cast more than 600 episodes ago. Are there any updates? Does Pluto have a chance of regaining planethood again?

Last week we talked about the various ways that astronomers could detect the presence of intelligent civilizations by observing technosignatures. This week we'll give you an update on the state of the search for extraterrestrials. This field has gone from a collection of pariahs to a completely legitimate field of research. What's changed?

Last week we talked about what it's going to take to confirm basic biological life across the Solar System and the Milky Way. This week, we'll discuss what it's going to take to detect intelligent life out there in space.

Are we alone in the Universe? It's one of the biggest scientific questions we can possibly ask. And yet, with rovers on Mars, missions planned to visit Europa and Ganymede. Powerful telescopes able to detect the atmospheres of exoplanets, we're closer than ever to finding out the answer.

Volcanos can be some of the worst natural disasters that we can experience here on Earth. But life wouldn't even exist without them. So, what are volcanos good for anyway?

As you all know, Pamela refuses to talk about any missions which aren't actually doing science. Well, Perseverance has crossed the line, from fantasy to an actual working rover, scooping regolith and yeeting helicopters. What has the rover accomplished in its first 100 days?

Mars is cold and dead today, but the massive volcanoes tell us what the planet used to be like, millions and even billions of years ago. But how volcanically active is the planet today? That's what NASA's Mars InSight lander is there to figure out.

Have you ever wanted to be a time traveler? Well, good news! You're time traveling right now. Into the future at one second per second. Taking too long? Don't want to wait? Good news, Einstein's got you covered. Today, let's talk about the weird world of time dilation. Also: There are monitor forts to consider… #MonitorFort And then there's a little something extra at the end just for you FullRaw listeners! - Rich

Last week we talked about balloon-based astronomy. This week we're gonna talk about putting telescopes on rockets and making observations mid flight. Welcome to the wild world of sounding rockets.

So when you think about the world's observatories, I'm sure you're imagining huge telescopes perched atop mountain peaks or space telescopes like Hubble. But you might be surprised to learn that some telescopes are carried high into the atmosphere on board balloons. What can they accomplish?

Last week we talked about how new telescopes and techniques are allowing astronomers to explore the shortest wavelengths of light. This week we go to the other end of the electromagnetic spectrum and explore the longer radio waves which are now accessible to astronomers.

The Earth's atmosphere protects us from a Universe that is definitely trying to kill us. But it also blocks our view of the entire cosmos, like seeing X-rays and gamma radiation. Space telescopes are changing our view of the most extreme events in the Universe.

Day by day we're loosing our connection with the night sky. Already one third of humanity lives in so much light pollution that they can't see the Milky Way without a drive. And now satellite constellations are adding additional light pollution, even in the darkest skies on Earth.

Today we are gonna gaze into the future of space and astronomy. What upcoming missions & events are we excited about?

Pamela has told us in the most flowery terms about the diffuse dust across the inner solar system left over from the formation of the inner planets. well, it turns out she was wrong. Super wrong. Time to update!

You've probably heard of dark matter and dark energy, but maybe you don't fully understand what they are. Or maybe the idea itself just rubs you the wrong way and you'd like to know why scientists think they can just make stuff up like this. So you'd like to overturn cosmology? Here's all you need to do.

It's been a while since we checked to make sure the Universe was still expanding. Yeah, apparently, that's still a thing. But in the last few years powerful new telescopes and expansive surveys have given us much more knowledge about what's happening. Especially at the earliest times.

You might be familiar with the cosmic microwave background, but that's just one of the background radiations that astronomers look at. Some are well known and cataloged. While others are just starting to be possible to see at all. All of them tell us more about our Universe.

This is gonna be another one of those evergreen topics where we come back again and again. Finding planets. Every time we talk about this now it seems like we've gained thousands of new planets. Well, buckle up! New techniques will grow that by tens of thousands and even millions!

Pamela is always loath to talk about spacecraft until the mission's in space and the science is rolling. NASA's Juno Mission just received a mission extension, adding Jupiter's moons to the menu. Now, finally, we can talk about Juno! [Ed. Juno what I mean?]

Stars often come in groups of 2 or more. And if they're orbiting close enough to each other one star can feast on the other and when that happens, well, mayhem ensues!

Some of the most powerful explosions in the Universe are gamma-ray bursts, capable of blasting a beam of death half way across the galaxy. In just the last few years astronomers have discovered a tremendous amount about these blasts and what's actually causing them. The answer, of course, is that it's more complicated than we originally thought. The old Gamma-Ray bursts show: http://www.astronomycast.com/2007/05/episode-36-gamma-ray-bursts/

Remember the good old days when there were only a few thousand living and dead satellites? Well, those days are long over. We're now entering an era where there will be tens of thousands of satellites. Not to mention the spent rocket boosters and other space junk. What kind of risk do we face and what can be done about it?

2024 can't come soon enough. You know, that's the year when humans will set foot on the Moon again. Now don't you roll your eyes! That's the plan. Unless the plan changes. But my point is, explorers going to the Moon will need to be concerned about all kinds of hazards, like dust, radiation and gigantic Moon worms. I believe.

We've talked about the Moon and its water many times here on Astronomy Cast, but there've been a bunch of big updates thanks to new research from NASA and others. Today we're gonna give you an update on the state of water on the Moon and the plans to take advantage of it.

All eyes are on the Moon. We're going back, this time to stay, right? One of the best resources on the Moon will be the lava tubes that criss-cross the subsurface of the Moon. These can provide protection from space, and a look at the geologic history of the Moon, and they can be enormous!

So the Moon is about to become a very busy place with multiple countries and private companies planning missions in the next few years. It's been decades since the Outer Space Treaty was negotiated. It's time for the Artemis Accords!

As scientists continue to explore the Earth, they're discovering life, surviving and even thriving in extreme environments. What hints can this give us about what we might find as we search for live on other worlds.

Astronomers are finding even more new extrasolar planets and they're starting to discover entirely new categories. There are classes of planets out there that we just don't have any analog here in the solar system. Let's talk about them!

So with a sample of asteroid Bennu firmly inside OSIRIS-REx's return capsule, it's time to bring this treasure home. So scientists can study the composition and history of the space rock. But it's not the only sample return mission out there, with Japan's Hayabusa II mission also bringing asteroid debris home. So today, let's talk about the missions and what we've learned so far.

This year's Nobel Prize in Physics was awarded to three brilliant researchers who worked out some of the secrets of black holes. Today we're going to talk about the chain of discoveries that led to this award.

Did you hear the news? Nobel prizes for Black Holes! Now, we know there are stellar mass black holes and supermassive black holes, but how do you get from one to the other? How do black holes get more massive?

Don't ever accuse us of not comprehensively covering every kind of exploding star. This week we gather up all the left over ways that stars partially or fully explode or don't. Probably. Enjoy!

So you think that a white dwarf star is the end of a stellar life, and it's all downhill from there, a long, slow cool down towards the end of everything. But in some situations even dead stars can get exciting again, briefly becoming some of the brightest objects in the Universe. And maybe, just maybe, the last exciting thing that'll ever happen in the Universe.

I've got some bad news for you. Stars die. At some point in the next few billion years or so our Sun is going to start heating up, using up all the fuel in its core, and then eventually die, becoming a white dwarf. It'll then slowly cool down to the background temperature of the Universe, becoming a black dwarf. Let's learn about this fascinating process.

So have you heard the news? Of course you have. Evidence of phosphene on Venus. Which could be a biosignature of life on our evil twin planet. There have been a lot of surprising stories about Venus, so let's get you all caught up!

Every 2 years or so Mars lines up nicely with the Earth. It takes only 2 minutes to communicate with the rovers. You can see the polar ice caps in a small telescope. And it's the best time to send your spacecraft to the Red Planet.  Oct 3rd: Moon & Mars conjunction, 1.1° separation. Oct 6th: Mars opposition. Dec 21st: Jupiter/Saturn conjunction, 0.1° separation! Feb 18th "Percy" lands on Mars' Jezero crater.

It's time once again for Astronomy Cast to go on hiatus. You've got a couple months on your own to explore the night sky. But before we say goodbye, we'd like to make a few suggestions.

As amateur astronomers, we curse the Moon every month. Seriously! Why doesn't someone get rid of that thing! This week, something occurred to us. What if we actually pointed our telescopes at the Moon? What would we see? The Lunar "X" that Fraser talked about will be visible this Friday, June 26th! So go out with binoculars or a telescope and enjoy!

We imagine the asteroid belt as a place where all the rocks hang out in the solar system. But there are 2 huge bands of asteroids that orbit the Sun with Jupiter called the Trojans. And soon we may actually get a chance to see them up close!

Streamed live May 15, 2020. Discovering comets is one of the fields that amateurs can still make a regular contribution to astronomy. But more and more comets are getting found by spacecraft, automated systems and machine learning. This week we'll talk about how comets are discovered and how you can get your name on one!

Space is really far away, so when you send a satellite out into the void, that's pretty much the last you're going to be able to work on it. And if anything goes wrong, too bad, you're out a satellite. But a new test has shown that it's possible to actually visit and fix a satellite in space. Maybe we don't have to throw them all away after all.

As everyone knows, the Universe owes us a bright comet. There have been a lot of promising candidates, but in the end, they always fail to live up to our expectations. Comets keep on breaking up with us.

So much of our Solar System has been shaped by enormous collisions early on in our history. Seriously, the nature of every planet in the Solar System has some evidence of massive impacts during some point in its history.

Last month astronomers announced that they had detected a tiny asteroid that had been captured by the Earth's gravity well and had been sharing our orbit for a few years. Today, let's talk about the smallest moons in the Solar System.

White dwarfs are usually about 60% the mass of the Sun, so it was a bit of a surprise when astronomers found one that was almost exactly twice that. What happens when white dwarfs merge?

Pamela and Fraser discuss the implications of COVID-19 and it's changes on the world, and what we all can do during this time.

We lost a bright star here on planet Earth last week. NASA mathematician Katherine Johnson passed away at the age of 101, after an incredible career of helping humans land on the Moon. If you saw the movie Hidden Figures, you'll know what I'm talking about.

You might be surprised to hear that we've never done an episode of Astronomy Cast featuring Betelgeuse. Well, good news, this is that episode. Let's talk about the star, why it might be dimming, and what could happen if it explodes as a supernova.

A brand new telescope has completed on Maui's Haleakala, and it has just one job: to watch the Sun in unprecedented detail. It's called the Daniel K. Inouye telescope, and the engineering involved to get this telescope operational are matched by the incredible resolution of its first images.

We've been following this story for more than a decade, so it's great to finally have an answer to the question, why was supernova 2006gy so insanely bright? Astronomers originally thought it was an example of a supermassive star exploding, but new evidence provides an even more fascinating answer.

On the one hand, red dwarfs are the longest lived stars in the Universe, the perfect place for life to hang out for trillions of years. On the other hand, they're tempestuous little balls of plasma, hurling out catastrophic flares that could wipe away life. Are they good or bad places to live?

For the longest time astronomers could only study the skies with telescopes. But then new techniques and technologies were developed to help us see in different wavelengths. Now astronomers can study objects in both visible light, neutrinos, gravitational waves and more. The era of multi-messenger astronomy is here.

The other big issue at the AAS was the challenge that astronomy is going to face from all the new satellite constellations coming shortly. There are already 180 Starlinks in orbit, and thousands more are coming, not to mention the other constellations in the works. What will be the impact on astronomy, and what can we do about it?

This week we're live at the American Astronomical Society's 235th meeting in Honolulu, Hawai'i. We learned about new planets, black holes and star formation, but the big issue hanging over the whole conference is the protests and politics over the new Thirty Meter Telescope due for construction on Mauna Kea.

It's hard to believe it, but we survived another trip around the Sun. Now it's time to take the whole journey all over again, but with new news. Let's take a look at some of the space and astronomy stories we're looking forward to in 2020.

Huge surveys of the sky are finding more and more planets, stars and galaxies. But they're also turning up strange objects astronomers have never seen before, like Boyajian's star. Today we're going to talk about some unusual objects astronomers have discovered, and why this number is only going to go way way up.

Hi everyone, Producer Susie here. This weekend, December 21-23, 2019, we will be having our CosmoQuest Hangoutathon.  For 40 straight hours, our team will be bringing you guests, science and fun live on our channel. We are raising money to pay for our team to continue to bring you science, and for us to continue our citizen science programs, like the extremely successful Bennu Mappers from this past year, where over 3500 of you wonderful volunteers mapped over 14 million rocks on the asteroid Bennu, looking for a safe place for the OSIRIS-REx mission to grab samples to return to earth.  We want to keep doing projects like this - and we need your help to continue doing the science.  Please join us at twitch.tv/cosmoquestx starting 9am EST / 6am PST / 1400UTC. If you can’t tune in live, you can catch the replays on Twitch, and we’ll be trying our best to archive all of the content on YouTube after this weekend. We’re accepting donations at https://streamlabs.com/cosmoquestx As part of the Planetary Science Institute, we are a 501c3 non-profit, so all of your donations are tax deductible where the law allows.  Please watch, share and donate if you can, so we can keep bringing the science to you! Thank you for listening!

The Cosmic Microwave Background Radiation is the earliest moment in the Universe that we can see with our telescopes, just a few hundred thousand years after the Big Bang itself. What will it take for us to be able to fill in the missing gap? To see closer to the beginning of time itself?

Powerful observatories like Hubble and the Very Large Telescope have pushed our vision billions of light-years into the Universe, allowing us to see further and further back in time. But there are regions which we still haven't seen: the Cosmic Dark Ages. What's it going to take to observe some of these earliest moments in the Universe?

Last week we gave you an update on the formation of elements from the Big Bang and in main sequence stars like the Sun. This week, we wrap up with a bang, talking about the death of the most massive stars and how they seed the Universe with heavier elements.

The Universe started out with hydrogen and helium and a few other elements, but all around us, there are other, more proton-rich elements. We believe these heavier elements formed in stars, but which stars? And at what points in their lives? Today we'll update our knowledge with the latest science.

Few sciences have been able to take advantage of the power of computers like astronomy. But with all this computing power, you might be surprised to learn how important a role humans still play in this science.

Before we discovered other planets, our Solar System seemed like a perfectly reasonable template for everywhere. But now we see massive planets close to their stars, which leads you to the question, how does it all get there. Do the planets form in place or do they migrate around?

Things used to be so simple. Comets were snowballs from the outer Solar System, and asteroids were rocks from the inner Solar System. But now everything's all shades of grey. Astronomers have found asteroids that behave like comets and comets that behave like asteroids.

Once again, another place where the Universe is going to make this difficult for us. Proving, once and for all that there's alien life on another world. It should be straightforward, look for biosignatures, but it looks like there are natural sources that could explain almost any chemical we could hope to search for.

Our series on Universe weirdness marches on. This week we take a look at the habitable zone, and how things aren't as simple as we thought.

Our series on Universe weirdness continues, this time we learn how astronomers are struggling to make sense of the age of the Universe.

Just when the Universe was starting to make sense, the cosmos throws a curve ball at us. Astronomers have been trying to accurately measure the expansion rate of the Universe as far back as Hubble. It's been tough to nail down, and now astronomers are starting to figure out why.

As astronomers started to discover planets orbiting other stars, they immediately realized that their expectations would need to be tossed out. Hot jupiters? Pulsars with planets? We're now decades into this task, and the Universe is continuing to surprise us.

How old are Saturn's rings? They could be brand new, or they could be as ancient as the Solar System itself. Planetary scientists thought they knew the answer thanks to new data from Cassini, but new ideas are calling even that into question. 

Thanks to all the work from Hayabusa 2 and OSIRIS-REx, astronomers are getting a much better look at the smaller asteroids in the Solar System. It turns out, they're piles of  rubble... but fascinating piles of rubble. Let's talk about what we've learned so far.

Please help us keep bringing you content by going to http://survey.libsyn.com/astronomycast and filling out the survey, so Libsyn can find us sponsors for Astronomy Cast!

Astronomy Cast will be on hiatus for July and August. Don't worry, we'll be back in September, and we might just have surprises for you all along this summer! Don't forget you can still catch Pamela with Daily Space, rocket launches and specials on CosmoQuest's Twitch channel, and you can find all the space news and videos from Fraser at Universe Today! We usually record Astronomy Cast every Friday at 3:00 pm EDT / 12:00 pm PDT / 19:00 UTC. You can watch us live on here on AstronomyCast.com, or the AstronomyCast YouTube page.

Relativity is used in more day to day situations than you may realize. In this episode, we will count (some of) the ways. This episode is brought to you live from the All-Stars Star Party in Indian Wells, California.

It's summertime, and time for our annual Astronomy Cast hiatus. But that doesn't mean that the astronomy adventure has to end. Today we'll give you some tips and tricks for astronomy summer adventures.

Last week we talked about some ancient south African astronomy, so this week we'll talk about the state of modern astronomy in the southern part of Africa, which happens to be a great place with nice dark skies and a great view into the heart of the galaxy.

Let's move to another continent this week, and look at the astronomy that was going on in southern Africa in ancient times.

Last week we talked about how well the indigenous Australians followed the night sky. Well, it turns out, Australia is still an amazing place for astronomy. There are so many powerful observatories in Australia, and even more in the works.

This week, we focus on the archaeoastronomy of another part of the world, this time from the indigenous people of Australia. Another group of people whose lives depended on knowing what was happening in the sky from season to season.

South America, especially the Atacama Desert in Chile has become one of the best places in the world to put a telescope. It's dry, high, and the nights are clear. Today we'll talk about the monster telescopes already in operation in this region, and the big ones coming soon.

The Andes mountains in South America are a hotspot of astronomy today, but ancient peoples knew it was a great place for astronomy and lived their lives in tune with the night sky. Today we'll learn all about what they knew, and how they mapped the movements of the stars and planets.

Last week we talked about the ancient astronomy of the American Southwest. But this is actually Pamela's stomping grounds, and she's spent many a night perched atop mountains in this region staring in the night sky with gigantic telescopes. How does astronomy get done in this region today?

Ancient peoples had no light pollution, and they knew the night skies very well. In fact, they depends on them to know when to plant and when to harvest. Today Pamela talks about the archeoastronomical sites of the American Southwest.

Today, of course, we're going to talk about the announcement from the Event Horizon Telescope and the first photograph of a black hole's event horizon.

Even though they might be scattered around our planet, astronomers have way to come together to work out issues that face their entire field of study. It's called the International Astronomical Union, and they're the ones who work out the new names for stars, and sometimes de-planet beloved Kuiper Belt Objects.

We learned how to figure out the ages of objects in the Solar System, now we push out into the deeper Universe. What about stars, galaxies, and even the Universe itself? How old is it? This episode is part 3 of a series.

Today we push our aging curiosity out into the Solar System to ask that simple question: how old is it and how do we know? What techniques do astronomers use to age various objects and regions in the Solar System? This is part two of a series.

People always want to know how old everything is. And more specifically, they want to know how we know how old everything is. Well, here at Astronomy Cast, it's our job to tell you now only what we know, but how we know what we know. And today we'll begin a series on how we know how old everything is. This is part one of a double episode.

Recorded during the Astrotour to Costa Rica, Fraser talks to Dr. Paul Matt Sutter about the nature of dust and BICEP 2's claim of discovering primordial gravitational waves.

We always focus on the missions, but there's an important glue that holds the whole system together. The Deep Space Network. Today we're going to talk about how this system works and how it communicates with all the spacecraft out there in the Solar System.

This is our second episode in a two part series where we look at Transients in astronomy. In last week's episode, we talked about things that change here in our own Solar System. Now we'll talk about everything else in the Milky Way and beyond.

Astronomers have found that sometimes the Universe changes. Things move, things explode, things get brighter or dimmer. In fact, knowing this has helped astronomers discover some very important aspects of the Universe. Today we begin a two part series on Transients and their role in astronomy.

We always say the Universe is trying to kill us. But there was this one time, when the Universe used our own fear of nuclear attack against us, nearly setting off a global nuclear war. Nice try Universe, we're on to you now.

One of the most influential astronomers in the 20th Century was Fritz Zwicky. He had his hand in the discovery of dark matter, gravitational lensing, supernovae and neutron stars. And he also worked on a few more controversial ideas like, uh, tired light. Let's learn more about Zwicky.

It's cold right now. Okay, fine, here on Vancouver Island, it's actually pretty warm. But for the rest of Canada and big parts of the US, it's terrifyingly cold. Colder than Mars or the North Pole cold. This is all thanks to the break up of the polar vortex. What are polar vertices, how do they form, and where else to we find them in the Solar System?

Space is a hostile environment in so many ways. But one of its worst features is the various kinds of radiation you can find. When astronauts go back beyond the protective environment of the Earth's magnetosphere, what are the various kinds of radiation they'll encounter. And is there anything we'll be able to do about it?

As we send rovers and landers to other worlds, we have to think about the tiny microbial astronauts we're sending along with us. In fact, NASA is so concerned about infecting other worlds that it has established the planetary protection protocols. Just to be safe.

The Sun. It's a big ball of fire, right? Apparently not. In fact, what's going on inside of the Sun took us some time and knowledge of physics to finally figure out: stellar fusion. Let's talk about the different kinds of fusion, and how we're trying to adapt it to generate power here on Earth.

Finding planets is old news, we now know of thousands and thousands of the places. But the terrible irony is that we can only see a fraction of the planets out there using the traditional methods of radial velocity and transits. But the new telescopes will take things to the next level and image planets directly.

We did it, we made it through 2018 in space. Now let’s look forward to the incredible launches, discoveries and astronomical events happening in 2019.

2018 was an incredible year in space news. Rockets launched, landers landed, spacecraft were born and died. We learned tremendous new things about Universe around us, and today we're here to look back fondly over the last 12 months to review the year in space that was.

The technology of 3D printing is taking off. From tiny home-based 3D printers to larger manufacturing. And of course, 3D printing is going to space with the International Space Station and beyond.

We did it, we made it to the end of another year. Once again it's time to wonder what gifts to get your beloved space nerds. We've got some suggestions. Some are brand new this year, others are classics that we just can't help but continue to suggest. Let's get into it.

Ion engines are a mainstay of science fiction, featured in both Star Trek and Wars. But this is a very real technology, successfully used on several missions out there in the Solar System right now. How do they work and what are the limits?

Did you hear that astronomers from Harvard think that the interstellar asteroid Oumuamua was actually an alien solar sail? Is it aliens? Of course it's not aliens. But some day, it'll actually be aliens.

We're always interested in the surface features of the planets and moons in the Solar System, but that's only skin deep. It turns out, these worlds have an interesting inner life too. Thanks to the science of seismology, we can peer into our planet and learn how it works... inside. And we're about to take that technology to Mars.

To really study something, you want to reach out and touch it. But what can you do if you're separated by a huge distance? You reach out with electromagnetic or sound waves and watch how they bounce back. Thanks to radar, sonar and lidar.

The Earth looks like a perfect sphere, but down here on the surface we see that there are mountains, rivers, oceans, glaciers, all kinds of features with different densities and shapes. Scientists can map this produce a highly detailed gravity map of our planet. And it turns out, this is very useful for other worlds too.

How do you know what something is made of if you can't reach out and touch it? How do we know what planets lights years away have in their atmosphere? What about the rocks all around Curiosity? Or the geysers coming out of Europa and Enceladus? Scientists have a few handy tricks.

We're not learning that the vast majority of potentially habitable worlds out there are actually icy moons like Europa and Enceladus. Good news, there are hundreds, if not thousands of times more of them than worlds like Earth. Bad news, they're locked in ice. What have we learned about water worlds and their potential for habitability?

Welcome to episode 500 of Astronomy Cast. To celebrate this momentous occasion, we're going to look back 500 years into the past to see what we learned about the Universe. And then we're going to look 500 years into the future. Astronomy Cast celebrated their 500th episode on Sept 15-16, 2018. We broadcasted from our celebration, in front of a live audience! And we debuted our new theme music by composer, fan and friend David Joseph Wesley!

We started out Astronomy Cast with the controversal decision to de-planet Pluto. And here we are, more than a decade later, at the brink of recording our 500th episode when another big decision is coming down from the IAU: whose name goes on the concept that our Universe is expanding: Hubble or Lemaître? It’s a big deal and Pamela knows all about it.

The Milky Way has gobbled up dozens of dwarf galaxies and added them to its structure. Today we're going to look at the ongoing hunt for the wreckage of past mergers. And what we've discovered about dwarf galaxies in general.

Is it globular clusters or is it globeular clusters? It doesn't matter, they're awesome and we're here to update you on them.

Another update show, this time on the various generations of stars, let's get into it.

Our knowledge of space is starting to match up with our ability to get out there an explore it. There are several companies working on missions and techniques to harvest minerals from asteroids. What other resources are out there that we can use?

Thanks to Cassini and other spacecraft, we've learned a tremendous amount about the icy worlds in the Solar System, from Jupiter's Europa to Saturn's Enceladus, to Pluto's Charon. Geysers, food for bacteria, potential oceans under the ice and more. What new things have we learned about these places?

If there's one place we've learned more about in the last 10 years, it's Mars. Thanks to all those rovers, orbiters, landers which are flying overhead, crawling around the surface, and digging into the rich Martian regolith. What have we learned about Elon Musk's future home?

Another topic with plenty of updates. Since we started Astronomy Cast we’ve visited many smaller objects in the Solar System up close, from Ceres and Vesta to Pluto, not to mention a comet. What have we learned?

Finally, a big update. Have there been news in the realm of exoplanets? More news that we can possibly cover. But we'll try our best.

Time for another update, this time we're going to look at what's new with supernovae. And once again, we've got good news, lots of new stuff to report.

Another update episode, this time we look at what’s new and changed in the research of black holes. And it’s here that we find a lot of substantial new discoveries in the field, so much has been discovered since we first covered black holes a decade ago.

The updates continue. Last week we talked about dark matter, and this week we continue with its partner dark energy. Of course, they're not really partners, unless you consider mysteriousness to be an attribute. Dark energy, that force that's accelerating the expansion of the Universe. What have we learned?

Last week, we gave you an update in particle physics. This week it's time to see what's new in the world of dark matter. Spoiler alert, we still have no idea what it is, but maybe a few more ideas for what it isn't.

It's time for a news update. This time from the field of particle physics. It turns out there have been all kinds of new and interesting particles discovered by the Large Hadron Collider and others. Let's get an update from Pamela.

It's one thing to get to space. But once you've made it there, what do you want to do? You'll probably want to dock with another space ship, deliver cargo, refuel. Today we'll talk about how all that happens.

If you want to get around in the Solar System, you'll want to take advantage of natural gravitational speed boosts and transfer orbits. Whether you're heading to the outer Solar System or you want to visit the Sun itself, the planets themselves can help you in your journey.

It's one thing to get from Earth to space, but sometimes you want to do the opposite. You want to get into orbit or touch down gently on the surface of a planet and explore it. How do spacecraft stop? And what does that even mean when everything is orbiting?

Getting to space is all about rockets, but people are trying to figure out other methods that could carry payloads to orbit and beyond. Railguns, airplanes, tethers and more. Today we’ll talk about alternative methods of spaceflight.

Pamela will be on to answer your space and astronomy questions live, as Fraser enjoys auroras in Iceland this week!

The vast majority of rockets are multi-staged affairs. Why is this? What makes this kind of rocket so successful? Today we look at the ins and outs of multi-stage rockets.

To celebrate the launch of the Falcon Heavy, we figured it was time for an all new series, this time on the rockets that carry us to space. Today we're going to talk about why single stage to orbit rockets are so difficult to carry out.

On Christmas Day, 1968 Frank Borman, James Lovell and William Anders became the first human being to see the far side of the Moon. Their mission, of course, was Apollo 8, the first time human beings had ever left Earth orbit and seen the far side of the Moon. Today we talk all about Apollo 8, with special guest Paul Hildebrandt, director of a new documentary about the mission.

It's been decades since humans set foot on the Moon. Well, it's time to go back, in theory. Of course, we've heard this all before. What are the plans afoot to send humans back to the Moon this time. What hardware will we use, and what other strategies are in the works to make this happen?

After they’ve been to space, many astronauts report that seeing the world from above has given them a totally new perspective on humanity and the state of our planet. It’s called the Overview Effect. Today we’ll talk about this, and what this perspective can teach us all.

You know what’s fun? Mysteries. Here’s one: fast radio bursts. Astronomers have been detecting mysterious one-time signals from across the sky. What’s causing them? Nobody knows for sure, but the search is on to get to the bottom of them.

Phew, 2018, time to press the reset button and enjoy a whole new year of space exploration and space science. What’s coming up this year? What should we expect to launch, and what will we see in the sky?

2017 was a crazy year for, well, you know. But, it was a great year for space science, a kilonova, extrasolar planets, reusable rockets and more. Let's look back at the year that was and remember our favorite space science.

What happens when the future meets biology? Bioscience science fiction, of course. And that's our focus today as we continue our journey though science-based science fiction.

It's time to talk computers, and how we're going to be dealing with them in the future. In our next segment on modern sci-fi, we talk about the future of the human-computer interface.

Our journey through interesting science fiction, this time we talk about speculative fiction dealing with materials science, nanotechnology and 3D printing. It’s a staple in Star Trek, but what other stories deal with it?

We've always been fans of science fiction, but we really like our science. Today we'll talk about some books we've been reading recently that do a good job of dealing with the science in science fiction.

Astronomers depend on simulations to study the Universe. From relatively straightforward orbital simulations to vast simulations that try to recreate the large scale structure of the Universe from the Big Bang. Today we're going to talk about some of those simulations, as well as tools you can use simulate the Universe.

Many of the moons and planets across the Universe are in resonance with each other and their star. What causes this resonance, and how can it help us understand the history of planetary formation and migration?

We depend on zero for our math to work right, but this number was actually invented in fairly recent times. Why do we need zero? Was it inevitable?

Electromagnetic radiation, also known as "light" is pretty handy for astronomers. They can use it to directly and indirectly observe stars, nebula, planets and more. But as you probably know, light can act like a wave, creating interference patterns tto teach us even more about the Universe.

Astronomers this week announced that they had discovered an asteroid or comet on a trajectory that brought it from outside the Solar System? Is this the first case of an object from deep space? And what can we learn from this discovery?

The man in the moon, the pyramids on Mars. Every cloud, ever. Humans have a tendency to pattern match when they're looking around the Universe - it's called pareidolia. What causes this behavior, and how can we use this to debunk some hilarious conspiracy theories?

Have you noticed that weather forecasting has gotten much better in the last few years? Thanks to weather satellites, weather stations, and better forecasting techniques. How do scientists predict the weather with any kind of accuracy days or even weeks in the future.

What's the weather doing? Is it going to rain today? How much? What about temperatures? We depend on modern weather forecasting, thanks, in part to the vast network of weather satellites. What instruments do they have, what orbits do they use.

The space age has given us the ability to look at every corner of the globe in every wavelength. It's revolutionized our ability to predict the weather, keep track of environmental damage, and watch the world change. Today we look at what missions and technologies give us the ability to watch our world from afar.

The iconic Arecibo Radio Observatory has been a mainstay in science and science fiction. This Puerto Rico-based radio telescope was already in an uncertain level of funding. But now with the damage from Hurricane Maria, it might be shut down forever.

And now Cassini’s gone. Smashed up in the atmosphere of Saturn. But planetary scientists are going to be picking through all those pictures and data for decades. Let’s look back at some of the science gathered up by Cassini so far, and we can still learn from this epic journey.

It's time to say goodbye to an old friend, NASA's Cassini spacecraft, which has been orbiting within the Saturnian system since 2004. But why does a seemingly healthy spacecraft and mission need to come to an end? Today we look back at the mission, some of the amazing discoveries, and why its finale was necessary.

This week, we return to our starting point, where Astronomy Cast began: Pluto. 11 years on, we have a whole new appreciate for the dwarf planet Pluto. We've visited it, probed it and taken pictures. It's time for an update.

This episode was recorded live in St. Louis, MO at the Astronomy Cast Solar Eclipse Escape 2017. Listen as we discuss how humans might be able to colonize the Milky Way!

As we wrap up season 10 of Astronomy Cast, we look forward to all the instruments, missions and science results on the distant horizon. Think astronomy is exciting already? Just you wait.

10 years of Astronomy Cast... wow. It's been a long, fun journey. What are some of our favorite episodes and adventures over the decade we've been doing this show.

Summer is almost here, and for the northern hemisphere, that means warm nights for observing. But what to observe? We're here with a list of events and targets for you to enjoy over the summer. Get your calendars handy, and start organizing some events with your friends, and then get out there!

Like most of us, you probably want to know what it would be like to travel to space. Maybe not to live, but just to visit. You want to be a space tourist. Good news, there are a bunch of companies working hard to give you the opportunity to fly to space. How long until you can buy a ticket?

In order to live in space, we'll need to live in a habitat that simulates the temperature, pressure and atmosphere of Earth. And one of the most interesting ideas for how to do this will be with inflatable habitats. In fact, there are a few habitats in the works right now, including one attached to the International Space Station.

When you think of a robot, you're probably imagining some kind of human-shaped machine. And until now, the robotic spacecraft we've sent out into space to help us explore the Solar System look nothing like that. But that vision of robots is coming back, thanks to a few new robots in development by NASA and other groups. 

On Monday, August 21, 2017, there's going to be a total eclipse of the Sun, visible to path that goes right through the middle of the United States. You should be making plans to see this, and we're here to help you know where to go and what to do.

For the final episode in our 3-part episode about animals in space, we look at the largest animals to go to orbit. And I'll just warn you now, this is going to be a really sad episode.

Last week we talked about how the smallest creatures behave in space, but now we move up in size a little to small animals, like mice. What missions have they flown on, and how does microgravity affect their biology?

We've talked about animals traveling to space in the past, but it's time to take another look, with many other creatures making the trip to the void. Today we're going to talk about the spineless insects and arthropods, and those tough as nails waterbears – tardigrades.

For this historic 444th episode of Astronomy Cast, we talk about fractals. Those amazing mathematical visualizations of recursive algorithms. What are they, how do you get them? Why are they important?

Want to travel the world but you don't have a lot of money? No problem, your continent is drifting across the surface of the Earth right now. In a few million years, you'll reach your destination.

There are regular volcanoes, and then there are the supervolcanoes. Massive calderas of hot magma of incomprehensible size. Bad news, these things explode randomly and catastrophically. Worse news, there are a bunch around the Earth.

We always want to talk about how we can make Mars more Earth like, but the reality is that we're making Earth more Venus-Like. We're Venusforming Earth. What are the various factors we're impacting on a global scale, and how can we fix them?

We know humans are having an impact on planet Earth, but what if we really put our backs into it, and intentionally tried to change the entire planet? Either to make it better, or to fix some terrible mistake we've made. The technique is called geoengineering. Could it work?

We love to destroy the universe, and also rebuild it. Today we begin a new series where we destroy and rebuild. Let's talk about some existential threats we face, and ways we could recover, starting with the sword of Damocles hanging over our head: killer asteroids!

Surf's up! Today we're going to be talking about one of the most devastating natural disasters out there: tsunamis. We're talking huge waves that wreck the seashore. But it turns out, there many ways you can get a tsunami, and one of those has to do with space.

If we look back into the geologic record of the Earth, it appears that our planet’s magnetic field flips polarity every few hundred thousand years or so. Why does this happen? When’s it supposed to happen next? Is it dangerous?

Astronomical Night Before Christmas, pt. 3, by Pamela Gay

This week the shows include: Dec 08: A New Look at the Drake Equation by David Black; Dec 09: Mercury’s Volcanoes by Bob Hirshon, AAAS; Dec 10: Aryabhatta by Brains Matter; Dec 11: Europa's Oceans and Possible Life by AstronomyCast; Dec 12: 'Twas the Observer's Day Before Christmas by Pamela Gay; Dec 13: Encore: Exploring Space with Your Computer by Bruce Irving; Dec 14: Aliens in Fact and Fiction by Walden School.

This week the shows include: Dec 01: Familiarity Breeds Apathy by Manoharan Karthigasu; Dec 02: Naming Stars by Walden School; Dec 03: The Yerkes Telescope and Observatory by Alan Agrawal; Dec 04: Encore: The Tradition of Looking Up by Chad Moore and Angie Richman; Dec 05: Light Speed by Steve Nerlich; Dec 06: Top Ten Best Things to Look at in the Sky by Carolyn Collins Petersen; Dec 07: Astronomy for Everybody by John Johnson.

This week the shows include: Nov 24: Mars Science Laboratory by Tony Rice; Nov 25: Encore: Seeing the Universe in a Whole New Light by Nicole Gugliucci; Nov 26: Black Holes: Everyone's favorite physics experiment by Steve Nerlich; Nov 27: Black Holes: The Supermassive Ones by Steve Nerlich; Nov 28: Tycho Brahe's Uraniborg by Adam Fuller; Nov 29: Four Small Constellations in the Northern Hemisphere by L. Cate Kendal; Nov 30: Observing With Webb in December 2011 by Rob Webb.

This week the shows include: Nov 17: Solar Cycles by NOAO; Nov 18: Indigenous Australian Astronomy by Steve Nerlich; Nov 19: Under a Story Sky by David Ault; Nov 20: How Cold is the Moon? by The NASA Lunar Science Institute; Nov 21: Observing With Webb: Telescopes For Christmas For Beginners by Rob Webb; Nov 22: Encore: Globular Star Clusters: How Old Am I? Where Are You? by Richard Kinne; Nov 23: Flying to Mars by Rob Knop.

This week the shows include: Nov 10: Galaxy Hunting by Carolyn Collins Petersen; Nov 11: MESSENGER Overturns Origin of Mercury by Bob Hirshon, AAAS; Nov 12: Questions from Class 2R by Steve Nerlich; Nov 13: An Astronomical Trifecta in 2012 by Michael Zeiler; Nov 14: Countdown for Upcoming Solar Eclipses by Jay Pasachoff; Nov 15: CMU Physics Concepts Program: Decades-long Outreach to Middle Schools by Diane Turnshek; Nov 16: October 25th 2011 Solar Show by RapidEye.

This week the shows include: Nov 03: ALMA: The building blocks of something great by Adam Avison; Nov 04: The Role of Spruce Pine Quartz in Astronomy by David Biddix; Nov 05: An Inside Look at the NASA Lunar Science Institute by The NASA Lunar Science Institute; Nov 06: Observing With Webb in November 2011 by Rob Webb; Nov 07: Dirty Snowballs & Giant Planets: X-Ray Secrets of Our Solar System Revealed by The Chandra X-Ray Observatory; Nov 08: Open Notebook Astronomy by Sandy Antunes; Nov 09: Encore: Celebrating Carl Sagan's Birthday with Longtime Collaborator Ann Druyan by Matt Kaplan.

This week the shows include: Oct 27: Space Dust by Jackie Villadsen; Oct 28: Introduction to Astrophotography by Adam Pender; Oct 29: Bang! A Comic About How All Things Came To Be by Paul Caggegi; Oct 30: Encore: An African Boy's Heavenly Dream by Abraham Samma; Oct 31: Sprite: A Spacecraft for All by Maurizo Moribito; Nov 01: Why the LHC Won't Kill You by Steve Nerlich; Nov 02: Black Hole Formation in the Early Universe: Q & A with Marta Volonteri by Chris Lindsay.

This week the shows include: Oct 20: Plan for a Sustainable Lunar Base by The NASA Lunar Science Institute; Oct 21: Stargazing 101: Help Topics for Beginners by Julio Vannini; Oct 22: Encore: How Lunar Cycles Affect Wildlife by Wild Ideas; Oct 23: Encore: Warp Drive by Renata and Damian Handzy; Oct 24: Don Quixote by Steve Nerlich; Oct 25: Visualizing the Expanding Universe by Rob Knop; Oct 26: Saturn's Moon Phoebe by Thomas Hofstätter and Leon Dumbroski.

This week the shows include: Oct 13: Dialogue Concerning the Two Chief Color Views of the Sun by George Cooper and Mike Edwards; Oct 14: Hollows on Mercury by Bob Hirshon, AAAS; Oct 15: Encore: Voyager: Sailing to the Edge of our Solar System by Jane Platt from JPL, with Dr. Ed Stone; Oct 16: An Account of Truman Kohman's Life and Love of Astronomy, 1916-2010 by Diane Turnshek; Oct 17: The Acclerating Universe and the Nobel Prize by The National Optical Astronomy Observatory; Oct 18: The Vital Importance of the Moon for Life on Earth by Damian Lima; Oct 19: An Interview with George Diller, the Voice of NASA by Tony Rice.

This week the shows include: Oct 06: Encore: Looking for a reason. Why Astronomy? by Richard Saunders; Oct 07: What's up in Planetary Exploration in October 2011 by Emily Lakdawalla; Oct 08: Magnification by Telescope Man; Oct 09: Encore: Stars That Fell Like Rain by John Johnson; Oct 10: Critical Density by Steve Nerlich; Oct 11: Technology Boosts Astronomy Education and Outreach by The 365 Days of Astronomy Podcast 2011; Oct 12: The Discovery of the Accelerating Universe by Rob Knop.

This week the shows include: Sep 29: Science Fiction and Science Fact by Katie Peterson/Adler Planetarium; Sep 30: Observing With Webb in October 2011 by Rob Webb; Oct 01: Look for the Bunny Girl: How NASA's Missions to the Moon Influence the Imagination by Jessica Santascoy; Oct 02: Encore: Kepler Keeps on Giving by Roz Brown/Ball Aerospace; Oct 03: ALMA Opens Her Eyes by Tania Burchell/NRAO; Oct 04: Why Comet Elenin is NOT a Brown Dwarf Star by Tony Darnell; Oct 05: International Observe the Moon Night 2011 by The NASA Lunar Science Institute.

This week the shows include: Sep 22: Carnival of Space #215 -- the podcast by Steve Nerlich; Sep 23: A Star Party With A Noisy Astronomer – An Interview With Nicole Gugliucci by Kylie Sturgess; Sep 24: Wonders from Class, Part 4: Labs by Diane Turnshek; Sep 25: Historical Maps of Solar Eclipses from 1654 to Today by Michael Zeiler; Sep 26: Light Pollution by Telescope Man; Sep 27: Wavelengths - More than Meets the Eye by Steve Nerlich; Sep 28: Wavelengths - The Long and the Short of It by Steve Nerlich.

This week the shows include: Sep 15: Encore: New World Ordered by Daniel Raffaele; Sep 16: Can Habitable Planets Be Found Orbiting White Dwarf Stars: Q & A with Eric Agol by Chris Lindsay; Sep 17: Planet Host Stars by The National Optical Astronomy Observatory; Sep 18: Encore: Mars and the Red Stars by Tavi Greiner; Sep 19: New Uses for Old Radio Dishes by Colm Ryan and Niall Smith; Sep 20: New Looks at the Apollo Landing Sites by The NASA Lunar Science Institute; Sep 21: A Backyard Boom: Thermonuclear Supernova in M101 by Rob Knop.

This week the shows include: Sep 08: Astronomy Outreach by Steve Nerlich; Sep 09: Menu for Mars by Bob Hirshon, AAAS; Sep 10: Measure the Sun by Sandy Antunes; Sep 11: The Truth in Science and Astronomy by Elmar von Agris; Sep 12: Astronomy Clubs: The How, What and Why by Daniel Elbert Herron; Sep 13: September Observing by Telescope Man; Sep 14: Measuring the Stars' Light by Thomas Hofstätter and Leon Dumbroski.

This week the shows include: Sep 01: The Moon Does not Spin on its Axis by Steve Nerlich; Sep 02: The Dark Energy Survey Project: Q & A with David Gerdes by Chris Lindsay; Sep 03: Fobos-Grunt by Steve Nerlich; Sep 04: The Dwarf Planets of the Outer Solar System by Joe Scaife; Sep 05: ENCORE: Observing Variable Stars by Travis Searle, Rebecca Turner and Mike Simonsen; Sep 06: The LCROSS Revolution by The NASA Lunar Science Institute; Sep 07: Encore: How Amazingly Unlikely Is Your Birth? by Larry Sessions.

This week the shows include: Aug 25: Henrietta Swan Leavitt by Steve Arnold; Aug 26: The Conditions Needed for the Inception by Life by Liminility; Aug 27: Wonders from Class, Pt. 3 by Diane Turnshek; Aug 28: Light - and a Bit of Dark by Steve Nerlich; Aug 29: Light - Wibbly, Wobbly Spacey-Timey Stuff by Steve Nerlich; Aug 30: Encore: The Magnetosphere by Terry and Stephen Whelan; Aug 31: Observing With Webb in September 2011 by Rob Webb.

This week the shows include: Aug 18: Wonders from Class, Pt. 1 by Diane Turnshek; Aug 19: Wonders from Class, Part 2 by Diane Turnshek; Aug 20: David Kring: Making an Impact on Earth and the Moon by The NASA Lunar Science Institute; Aug 21: ENCORE: Drifting Through the Zodiac by Christopher Crockett; Aug 22: Songs of Distant Earth by Darren Landrum; Aug 23: Detection of Visible Light from the Darkest World by David Kipping; Aug 24: Stars at a Glance by Thomas Hofstätter and Leon Dumbroski.

This week the shows include: Aug 11: Apollo 11: Coming Home by Thomas Hofstätter and Leon Dumbroski; Aug 12: Orbiting Between the Fire and Frying Pan by Bob Hirshon, AAAS; Aug 13: August Observing Tips by Telescope Man; Aug 14: Flock of Worlds by Adrian Morgan; Aug 15: Encore: Ptolemaic Cosmology - the Universe before Copernicus by Nik Whitehead; Aug 16: On the Success of Big Bang Cosmology by Rob Knop; Aug 17: The REU Program at NOAO by NOAO.

This week the shows include: Aug 04: Juno, New Frontiers to Jupiter by Tony Rice; Aug 05: A Look at NASA's Future Through an Astronaut's Eyes by The NASA Lunar Science Institute; Aug 06: What is a DOB? by Telescope Man; Aug 07: Encore: Adaptive Optics by Scott Kardel; Aug 08: Luminiferous Aether by Jim Bell from Sounds of Science; Aug 09: Encore: Why We Must Go to Mars by Robert Zubrin; Aug 10: A Tour of the Crab Nebula by The Chandra X-Ray Observatory.

This week the shows include: Jul 28: Tumble Into Darkness by Jeff Wood; Jul 29: Encore: Location, Location, Location! by Sue Ann Heatherly, of NRAO; Jul 30: Webb, James Webb by Steve Nerlich; Jul 31: Observing With Webb in August of 2011 by Rob Webb; Aug 01: The Planets in August by The Tecnocasters; Aug 02: Shakespeare’s Secret Knowledge of Astronomy by Mick Vagg; Aug 03: Apollo 11 Mission: On the Moon by Thomas Hofstätter and Leon Dumbroski.

This week the shows include: Jul 21: Apollo11: Part 2 - The Landing by Steve Nerlich; Jul 22: Auroras and the Solar Storm of 1859 by Liminality; Jul 23: The Sky Through Two Telescopes by George Kristiansen; Jul 24: Apollo11: Part 3 - Getting Back Again by Steve Nerlich; Jul 25: A Planet is a Peculiar Place by Maurizo Moribito; Jul 26: High School Teams Compete in Lunar Research by The NASA Lunar Science Institute; Jul 27: Ripped Apart by a Black Hole by Rob Knop.

This week the shows include: Jul 14: Iridium Flares by Kyle Kneisl; Jul 15: Discovery of Neptune's Thirteen Moons, Part 1 by Diane Turnshek; Jul 16: Apollo11: Part 1 - Getting There by Steve Nerlich; Jul 17: The Galactic Star Thief by NOAO; Jul 18: The Discovery of Neptune's Thirteen Moons, Part 2 by Diane Turnshek; Jul 19: The Mars Hoax by Telescope Man; Jul 20: Encore: The Case of the Lobate Scarps by Carolyn Collins Petersen.

This week the shows include: Jul 07: What's up in Planetary Exploration in July 2011 by Emily Lakdawalla; Jul 08: Prize Winning Planetary Research by Bob Hirshon, AAAS; Jul 09: Solar Cosmic Katrina and Chicken Little by Sandy Antunes; Jul 10: My Favorite Space Shuttle Missions by Steve Nerlich & Nancy Atkinson; Jul 11: Stargazing and Our Atmosphere by Maurice Kemp; Jul 12: A Bigger Boom by Rob Knop; Jul 13: Apollo 11: Flight to the Moon by Thomas Hofstätter and Leon Dumbroski.

This week the shows include: Jun 30: The Dark Side by Steve Nerlich; Jul 01: The Making of Makemake by Brains Matter; Jul 02: Holst's Planets by Michael Vagg; Jul 03: Apollo 11 Preparations by Thomas Hofstätter and Leon Dumbroski; Jul 04: A Research Station on Mars - The Boreas Project, Pt. 3 by British Planetary Society; Jul 05: Moon Zoo Science Update by The NASA Lunar Science Institute; Jul 06: Impact! by Megan Argo.

This week the shows include: Jun 23: How to see the Last Space Shuttle Launch by Daniel Elbert Herron; Jun 24: One Giant Leap For Mission Design by Bob Hirshon, AAAS; Jun 25: Astronomers are People, Too! by 'Ask An Astronomer!' Team; Jun 26: Astronomy Rant by Telescope Man; Jun 27: Snoopy the Space Beagle by Maurizo Moribito; Jun 28: A Research Station on Mars - The Boreas Project, Pt. 2 by British Planetary Society; Jun 29: Citizen Science and the Zooniverse Project by The Adler Planetarium.

This week the shows include: Jun 16: Space Travel or Health and Safety by Maurizo Moribito; Jun 17: The Data from the LSST by NOAO; Jun 18: Remembering the Spirit Rover with Scott Maxwell by Nancy Atkinson; Jun 20: Mentoring in Astronomy by Diane Turnshek; Jun 21: Apollo 11 -- The Astronauts' Backgrounds by Thomas Hofstätter and Leon Dumbroski; Jun 22: A Research Station on Mars - The Boreas Project, Pt. 1 by British Planetary Society.

This week the shows include: Jun 09: June Observing List by Telescope Man; Jun 10: Encore: Learning about Seasons in a Planetarium by Chuck Dibbs; Jun 11: Why I Killed Pluto and Why It Had It Coming! by Richard Drumm; Jun 12: Encore: Mysterious Moon Rocks by The NASA Lunar Science Institute; Jun 13: The Biggest Things in the Universe by Matthew Francis; Jun 14: Probing the Kuiper Belt and Beyond by Meg Schwamb and Brooke Simmons; Jun 15: Kepler's Laws of Planetary Motion by Steve Nerlich.

This week the shows include: Jun 02: Has Saturn Swallowed His Children? by Michael Vagg; Jun 03: Herschel Space Observatory Science Update by Haley and Edward Gomez; Jun 04: Encore: What is Astronomy? by Carolyn Collins Petersen; Jun 05: Transit of Venus by Jay Pasachoff; Jun 06: An Unexplored World: Dawn Approaches Vesta by Emily Lakdawalla; Jun 07: Pillownauts by Heather Archuletta; Jun 08: James Webb: Inestimable Expectations by Ball Aerospace.

This week the shows include: May 26: Gravitational Waves by Rob Knop; May 27: Pan-STARRS1 by Niall Deacon; May 28: The Universe in your Phone by Pam Griffin; May 29: How to Build a Solar System by Steve Nerlich; May 30: 2011 Congressional Visits Day with the AAS by Diane Turnshek; May 31: End of an Endeavour by Pam Griffin; Jun 01: Taking Pictures of Mars with the Mars Reconnaissance Orbiter by Tanya Harrison.

This week the shows include: May 19: Encore: Pulsars by Stuart Lowe; May 20: Big Bang Pt. 1 - One Crowded Second by Steve Nerlich; May 21: Big Bang Pt. 2 - When the Dust Settled by Steve Nerlich; May 22: Gaze at the Moon Online by The NASA Lunar Science Institute; May 23: Binocular Astronomy by RapidEye; May 24: Fun Things to do in Our Solar System, Our Cosmic Paddling Pool by Paul Jones; May 25: The Square Kilometre Array for Australia by Brains Matter.

This week the shows include: May 12: How we Measure Distances to Stars and Galaxies by Damian Lima; May 13: Planetary Portraits and Spacescapes by Bob Hirshon, AAAS; May 14: Binoculars: A Low Cost Way to Start Observing by Telescope Man; May 15: Encore: Star Formation by Robert Simpson; May 16: Why the Alpha Magnetic Spectrometer-2 Experiment is Really Cool by Marcel-Jan Krijgsman; May 17: Big Black Holes by Rob Sparks and Dr. Dara Norman; May 18: Light Pollution: Causes, Effects and Solutions by Jason Davis.

This week the shows include: May 05: Alan Shepard: Astronaut and Moonwalker by The NASA Lunar Science Institute; May 06: The Science of Sunshine by Robert Berthiaume; May 07: Belinda Nicholson - The Stars Are Her Laboratory by Kylie Sturgess; May 08: The Night Sky in May 2011 by Telescope Man; May 09: What is the Future of Paid Science Journalism? by Sandy Antunes; May 10: Encore: The Informative Dwarf Planet Haumea by Darin Ragozzine; May 11: Planet Hunters by Meg Schwamb and Chris Lintott.

This week the shows include: Apr 28: A Thermal Tour of the Universe by L. Cate Kendal; Apr 29: The NASA Radio Jove Project by Steve Arnold; Apr 30: If You Are an Alien, Call Back Later by The Tecnocasters; May 01: Carolyn Herschel’s White Rose – NGC 7789 by RapidEye; May 02: Making Things Shorter and Slower by Steve Nerlich; May 03: Tracing Planetary Atmospheric Evolution Using Isotopes from Life, Pt. 2 by Adam Fuller; May 04: A Tale of Two Comets by Nick Howes.

This week the shows include: Apr 21: The Trans-en-Provence UFO Case by Michel Abrassart; Apr 22: Seeing With the Lens of Gravity by Matthew Francis; Apr 23: Encore: John Glenn’s Fireflies and the Astronauts’ Constellation by Robert Pearlman; Apr 24: Dusty Mysteries by The Witty Astronomers; Apr 25: Goodbye, Pioneer Anomaly by Kate Becker; Apr 26: Tracing Planetary Atmospheric Evolution Using Isotopes from Life by Adam Fuller; Apr 27: The Yuma Star Party by Rob Sparks.

This week the shows include: Apr 14: Central Florida for the Space Buff by Tony Rice; Apr 15: Our Sun by Brittani Taylor and Timothy Reilly; Apr 16: Aesthetics & Astronomy by Chandra X-Ray Observatory; Apr 17: Supermassive Black Hole Research by NOAO; Apr 18: Encore: Build it and They Will Come: Tale of an Observatory by Ted Judah; Apr 19: What are Those Strange Abbreviations on Star Charts? by Telescope Man; Apr 20: The Moon's Mysterious Exosphere by The NASA Lunar Science Institute.

This week the shows include: Apr 07: Unmanned Space Exploration in 2011, Pt. 2 by Emily Lakdawalla; Apr 08: The Venera Missions by Steve Nerlich; Apr 09: The Lion and The Ghosts by Ben Lillie; Apr 10: Ariane Rockets by Lycée Henri Moissan; Apr 11: Counting Lunar Craters by The NASA Lunar Science Institute; Apr 12: 108 Minutes by Artyom Doljikov; Apr 13: Exploring the Solar System: Asteroid Belt by Thomas Hofstätter.

This week the shows include: Mar 31: The life of Stars – A View of Orion by L. Cate Kendal; Apr 01: The Great Moon Hoax by Rob Knop; Apr 02: Exploring the Solar System: Mars by Thomas Hofstätter; Apr 03: Exótico Cielo Profundo: Through Markarian’s Chain by Sur Astronómico Julieta De Simone Shecre; Apr 04: A Copernican Gallop by Maurizo Moribito; Apr 05: Happy Nights: Dark Skies and Global Astronomy Month by The National Optical Astronomy Observatory; Apr 06: The Whole World in Your Hands by Rob Berthiaume.

This week the shows include: Mar 24: Project Icarus: Aiming for the Stars by Maurizo Moribito; Mar 25: Lunar Origins and Evolution with CLOE by The NASA Lunar Science Institute; Mar 26: Encore: Jupiter's Great Red Spot by Kevin Graham; Mar 27: Travel and Astronomy by Mr. Moose; Mar 28: Space Junk by Kate Becker; Mar 29: Solar Activity and Space Weather by The Adler Planetarium; Mar 30: The Universe and Your Computer by The Tecnocasters.

This week the shows include: Mar 17: The New Mosaic Imager at Kitt Peak by National Optical Astronomy Observatory; Mar 18: Sun-Earth Day 2011: Ancient Mysteries - Future Discoveries by Troy Cline; Mar 19: The Interplanetary Transport Network by Steve Nerlich; Mar 20: CMB: Origin of the Universe by Thomas Hofstätter; Mar 21: Galaxy Zoo 2 - Do Bars Kill Spirals? by Karen Masters and Chris Lintott; Mar 22: A Sneak-Peak on Variable Stars by Julio Vannini; Mar 23: MESSENGER Orbit Live! by Bob Hirshon, AAAS.

This week the shows include: Mar 10: Continuing Astronomy, pt. 2 by Stephen Uitti; Mar 11: MESSENGER Meets Mercury by Bob Hirshon, AAAS; Mar 12: Sunrise In Greenland by Rob Sparks; Mar 13: Space Music by Carolyn Collins Petersen; Mar 14: A MESSENGER to Mercury by Emily Lakdawalla; Mar 15: Stargate Universe and the Cosmic Microwave Background Radiation by Diane Turnshek; Mar 16: SCOPE – Citizen Science in Spectroscopy by Christi Whitworth.

This week the shows include: Mar 03: Meteorites in Antarctica by Brains Matter; Mar 04: The Origin of the Oceans by Steve Nerlich; Mar 05: The Lunar Laser Ranging Retro-Reflector: Over 40 Years and Going Strong! by The NASA Lunar Science Institute; Mar 06: Buying Your First Telescope by Telescope Man; Mar 07: GLOBE at Night 2011 by The National Optical Astronomy Observatory; Mar 08: Exploring the Solar System: Venus by Thomas Hofstätter; Mar 09: Musical Monkey Satellite-ing by Sandy Antunes.

This week the shows include: Feb 24: A Journey to the Centre of the Sun by L. Cate Kendal; Feb 25: Exploring the Solar System: Mercury by Thomas Hofsttter; Feb 26: Sneak Peek of the Springtime Skies by Jane Platt from JPL; Feb 27: Stardust at Tempel 1: The first Second Trip to a Comet by Emily Lakdawalla; Feb 28: Encore: Why Isn?t Pluto a Planet? by AstronomyCast; Mar 01: Supernovae at a Glance by Thomas Hofsttter; Mar 02: Getting into Astronomy, Pt. 1 by Stephen Uitti.

This week the shows include: Feb 17: Buckyballs in Space! by NOAO; Feb 18: Finding Exoplanets, Pt. 4 by Thomas Hofstätter; Feb 19: ARES: sleep, stress and space on the way to Mars by Maurizo Moribito; Feb 20: Going to the Moon with the Google Lunar X PRIZE by The NASA Lunar Science Institute; Feb 21: MyMoon: Engaging the Missing Link in Lunar Science and Exploration by The Lunar and Planetary Institute; Feb 22: Black Holes and the Cosmos by Carolyn Collins Petersen; Feb 23: More Things in Heaven and Earth by Rob Knop.

This week the shows include: Feb 10: Observing Galaxies from Radio Waves to Gamma-rays by Melanie Gendre; Feb 11: Super Sun Day by Bob Hirshon, AAAS; Feb 12: Studying Extremophiles on Earth to Understand Life in Space by Adam Fuller; Feb 13: Encore: We Are All Star Stuff by Carolyn Collins Petersen; Feb 14: Stardust: A Love Story by Kate Becker; Feb 15: Black Holes by The Carnegie Mellon University Astronomy Class; Feb 16: Twilight by Stephen Uitti.

This week the shows include: Feb 03: Backyard Astronomy in Leo by Martin Fanning; Feb 04: Junk Telescopes by Stephen Uitti; Feb 05: Drive a Rover with Exploration Uplink! by The NASA Lunar Science Institute; Feb 06: Junk Telescopes by Stephen Uitti; Feb 07: Hey, Light, Get Off of My Lawn! by NOAO; Feb 08: The “Other Stuff” in the Solar System by Rob Berthiaume; Feb 09: Encore: How Did the Earth Form by Stuart Clark.

This week the shows include: Jan 27: Astroimaging Under Light-Polluted Skies by Robert J. Vanderbei; Jan 28: StardustNeXT's Valentine's Day Date by Jane Platt from JPL; Jan 29: Light from Distant Galaxies by Carolyn Collins Petersen; Jan 30: Favorite Episodes from 2010 by The Tecnocasters; Jan 31: Life on Titan by Chris Impey; Feb 01: The Solar System Gets A Whole New Groove by Daniel Pendick; Feb 02: Meteor Detection by Radar for the Amateur Observer by Steve Carter.

This week the shows include: Jan 20: The Legacy of Apollo, with Andrew Chaikin by The NASA Lunar Science Institute; Jan 21: Finding Exoplanets, Pt. 2 by Thomas Hofsttter; Jan 22: Telescope Eyepieces by Edgardo Molina; Jan 23: Moon Colonies by Maurizo Moribito; Jan 24: It's All Downhill From Here by Steve Nerlich; Jan 25: Bringing NASA into your Classroom by Tony Rice; Jan 26: 7th Anniversary of Opportunity?s Arrival on Mars by Ken Brandt.

This week the shows include: Jan 13: Encore: The End of the Universe in 10 Minutes by AstronomyCast; Jan 14: Celebrate Your Favorite Solar System by Bob Hirshon, AAAS; Jan 15: 2012: The End of the World? by Diane Turnshek; Jan 16: Planck Releases its First Data by Chris North & Stuart Lowe; Jan 17: Staragazing With the Galileoscope by Rob Sparks, NOAO; Jan 18: What's New With Supermassive Black Holes by Rob Knop; Jan 19: Are We Alone? by Kate Becker.

This week the shows include: Jan 06: Shooting Stars Are Not Stars by Rob Berthiaume; Jan 07: Finding Exoplanets, Part 1 by Thomas Hofstätter; Jan 08: Untangling the Entanglement by Steve Nerlich; Jan 09: Music in a Rational Universe by Sandy Antunes; Jan 10: So you got a telescope? Pt. 2 by Jeff Gortatowsky; Jan 11: The Kepler Observatory at a Glance by Thomas Hofstätter; Jan 12: Unmanned Space Exploration in 2011 by Emily Lakdawalla.

This week the shows include: Dec 30: Earth-like Planet Hunters by The Tecnocasters; Dec 31: So You Got a Telescope? Part 1 by Jeff Gortatowsky; Jan 01: Welcome to 2011! by The 365 Days of Astronomy Team; Jan 02: Deep Into the Dipper! by Rob Keown and Tavi Greiner; Jan 03: Looking Up by Andy Briggs; Jan 04: Algol by Laura Higginbotham; Jan 05: Planetesimal-Driven Migration by The NASA Lunar Science Institute.

This week the shows include: Dec 23: Basic Spectroscopy for Amateurs, Pt. 2 by Mark DeVito and Tom Field; Dec 24: The Color of Stars by Rob Knop; Dec 25: Why Winter is So Cold by Rob Berthiaume; Dec 26: Mexico's First Exoplanet Discovery Using Life Sciences Algorithm by Edgardo Molina; Dec 27: Small Worlds by Emily Lakdawalla; Dec 28: The Eastern Sky by Natalie Hildebrandt & Grace Thornton; Dec 29: It Happened in 2010! by The Adler Planetarium.

This week the shows include: Dec 16: Celebrating the Light off Solstice by Judith Young; Dec 17: Planetary Science at AGU 2010 Conference by Bob Hirshon, AAAS; Dec 18: Is There Cosmological Evidence for God? by Stuart Clark; Dec 19: 2012: New Opportunities by Bill Hudson & Tiare Rivera; Dec 20: Aristarchus: The Copernicus of Antiquity by Adam Fuller; Dec 21: SpaceFest by Charles F. Dibbs; Dec 22: The Stay-at-Home?s Guide to the Galaxy by Steve Nerlich.

This week the shows include: Dec 09: Titan and the Saturnian System by Brains Matter; Dec 10: The Perils of Science News! by Sandy Antunes; Dec 11: The Mother of Love Imitates Cynthia’s Shapes by Mark Thompson; Dec 12: NASA’s Flying Observatory Begins Science Flights by Martin Ratcliffe; Dec 13: Art of Space by Carolyn Collins Petersen; Dec 14: The Death of a Universe by Ben Lillie; Dec 15: Lunar Crater Clues by The NASA Lunar Science Institute.

This week the shows include: Dec 02: 21st Century Thinking by Steve Nerlich; Dec 03: This Day In Astronomy History, Shatner Style by Arkle; Dec 04: The High End World of Reflector Telescope Optics by Edgardo Molina; Dec 05: The Birth, Life, and Death of Alien Planets by Daniel Pendick; Dec 06: Participating in Professional Science by Thomas Hofstätter; Dec 07: Ancient Astronomy; The Mayans by Augusto Valdés; Dec 08: Basic Spectroscopy for Amateurs by Mark DeVito.

This week the shows include: Nov 25: Showing the Family Around the Night Sky by Jeff Gortatowsky; Nov 26: The Space Shuttle Enterprise by Steve Nerlich; Nov 27: The Fight Against Light Pollution by Thomas Hofstätter; Nov 28: ALMA Update with Dr. Carole Lonsdale by Richard Drumm; Nov 29: Questions of a Stellar Nature by The Witty Astronomers; Nov 30: Oxygen at Rhea by The Tecnocasters; Dec 01: One Hundred Years of Citizen Science by Mike Simonsen.

This week the shows include: Nov 18: Are There Alternative Universes? by Stuart Clark; Nov 19: Gifts from the Sky by Sandy Antunes; Nov 20: Under a Dark Sky by David Ault; Nov 21: Astronomical Pictures of Science by Ben Lillie; Nov 22: The Most Massive Neutron Star by Rob Knop; Nov 23: Mysterious Moving Moon Dust by The NASA Lunar Science Institute; Nov 24: Differentiating Science From Spectacle by Jon A. McIntire.

This week the shows include: Nov 11: Too Much Light! by Carolyn Collins Petersen; Nov 12: Mercury is for Art Lovers by Bob Hirshon, AAAS; Nov 13: Harry Potter and the Night Sky by Bev Levene; Nov 14: Symmetries in the Universe by Renee Hlozek and David Marsh; Nov 15: The Mayan Calendar by Zachary Kessin and Julia Smith; Nov 16: Aliens in the Eyepiece by RapidEye; Nov 17: What's In a Science Meeting? by Emily Lakdawalla.

This week the shows include: Nov 04: A Tour of GOODS by Chandra X-Ray Observatory; Nov 05: Alpha-Omega presentation at Dragon*Con 2010 by Richard Drumm; Nov 06: The Mauna Kea Observatories by Thomas Hofstätter; Nov 07: New, Popular and Technical Astronomy Books by Slacker Astronomy; Nov 08: Powering Deep Space Missions by Steve Nerlich; Nov 09: Encore Edition: What is the World’s Largest Telescope? by Rob Sparks; Nov 10: Howling at the Moon, Pt. 2 by Richard Wright.

This week the shows include: Oct 28: Cassini?s Amazing Voyage to Saturn, it's Moons, and it's Rings by Andy Poniros; Oct 29: A Primer on High End Refractor Telescope Optics, Pt. 3 by Edgardo Molina; Oct 30: Spaceport America by The Tecnocasters; Oct 31: Space: What is it? by Alvin Ashworth; Nov 01: The Changing Universe by Jesse Rogerson; Nov 02: The "Goldilocks" Planet and Finding Planets by Rob Knop; Nov 03: The Art of Bringing Astronomy to the Public by Thomas Hofsttter.

This week the shows include: Oct 21: Connecting to Big by Ben Lillie; Oct 22: SETI Then and Now by Sue Ann Heatherly, of NRAO; Oct 23: Encore Edition: What if the Moon did not Exist? by Patrick McQuillan; Oct 24: Triple the Mission, Triple the Fun by Roz Brown/Ball Aerospace; Oct 25: SNOLab by Robert Berthiaume; Oct 26: Janet Mattei by Mike Simonsen; Oct 27: LCROSS and the Land of the Lunar Shadows by The NASA Lunar Science Institute.

This week the shows include: Oct 14: The Outer Limits by Steve Nerlich; Oct 15: Plutonomicon by Sandy Antunes; Oct 16: How the Sun Affects Us by Thomas Hofstäter; Oct 17: Can the Laws of Physics Change? by Stuart Clark; Oct 18: Criticism of the Drake Equation by Diane Turnshek; Oct 19: Goddard Dream Day by Daniel Pendick; Oct 20: Mysteria About Tycho Brahe by Thomas Hofstäter.

This week the shows include: Oct 07: Visualizing Epsilon Aurigae with Ryan Wyatt by Slacker Astronomy; Oct 08: Student Experiments Riding Aboard Shuttle by Bob Hirshon, AAAS; Oct 09: A Primer on High End Refractor Telescope Optics, Pt. 2 by Edgardo Molina; Oct 10: Astronews by Carolyn Collins Petersen; Oct 11: Why I Don’t Believe in UFOs: My Burning Questions by C. Augusto Valdés; Oct 12: Encore Edition: When the Universe Was Young by Richard Drumm; Oct 13: How to be a Lunar Scientist by The NASA Lunar Science Institute.

This week the shows include: Sep 30: Big Impact? by The Tecnocasters; Oct 01: The Gregorian Calendar by Zachary Kessin & Julia Smith; Oct 02: Downsizing the Universe! by Patrick McQuillan; Oct 03: Transiting Extra Solar Planets by Brains Matter; Oct 04: Life in the Universe: Odds and Expectations by André Gonçalves; Oct 05: Your Stellar Neighborhood by Steve Nerlich; Oct 06:  Extrasolar Planet Problems by AstronomyCast.

This week the shows include: Sep 23: Howling at the Moon by Richard Wright; Sep 24: A GPS System for Cosmic Images by Chandra X-Ray Observatory; Sep 25: A Closer Look at Galaxy Clusters by Thomas Hofstätter; Sep 26: A Primer on High End Refractor Telescope Optics, Part 1 by Edgardo Molina; Sep 27: Greenhouse Earth, Pt. 2 - The Restless Planet by Steve Nerlich; Sep 28: Near Earth Objects -- Not if, but When? by Roz Brown/Ball Aerospace; Sep 29: Mark and Marv's Excellent Egyptian Adventure by The Adler Planetarium.

This week the shows include: Sep 16: Is There Life on Mars? by Stuart Clark; Sep 17: Desert RATS: Humans and Robots Working Together by The NASA Lunar Science Institute; Sep 18: The Secrets of Star Birth by Daniel Pendick; Sep 19: They're Everybody's Stars by Carolyn Collins Petersen; Sep 20: Citizen Outreach in Astronomy by BOINC SETI; Sep 21: More Australian Archaeoastronomy by Steve Nerlich with Duane Hamacher; Sep 22: The September Equinox: All Latitudes Are Illuminated by Judith Young.

This week the shows include: Sep 09: Astronomy Club by Ben Lillie; Sep 10: Googling The Solar System by Bob Hirshon, AAAS; Sep 11: Amateur Astrophotography For Beginners by Richard Drumm; Sep 12: The Flight of Hayabusa by Emily Lakdawalla; Sep 13: How Much Damage Can You Do from Space? by Sandy Antunes; Sep 14: A Tribute to John Dobson on his 95th Birthday by Andy Poniros; Sep 15: Star Parties by RapidEye.

This week the shows include: Sep 02: Exótico Cielo Profundo: By the border of Vulpecula-Sagitta by Julieta De Simone Shecre; Sep 03: Joining forces and collaboration: FEDAM by Edgardo Molina; Sep 04: Exoplanet Roundup by Davin Flateau; Sep 05: The Nordlinger Ries: A Deep Impact in the Heart of Europe by Colm Ryan; Sep 06: Astronomy Vacations by Diane Turnshek; Sep 07: Greenhouse Earth Part 1 - The Inconstant Sun by Steve Nerlich; Sep 08: Discovering the Beauty of the Sky by Alexis Dwyer, Janet Barajas, Drew Olvey, and Micol Christopher.

This week the shows include: Aug 26: The search for extraterrestrial life ? vox pops by Marc West; Aug 27: Fom Galileo to Pluto's Demotion- two good reads for the end of summer by Sue Ann Heatherly, of NRAO; Aug 28: An Introduction to Space Exploration by Gordon Houston; Aug 29: The Search for Intelligent Life by Marc West; Aug 30: Astronomy and the iPhone by The Tecnocasters; Aug 31: Apollo 11 Conspiracy by Thomas Hofsttter; Sep 01: International Observe the Moon Night by The NASA Lunar Science Institute.

This week the shows include: Aug 19: Spacecraft Navigation by Steve Nerlich; Aug 20: Music on a Planetary Scale by Sandy Antunes; Aug 21: Astrophysics from the Moon by The NASA Lunar Science Institute; Aug 22: String Theory by Micol Christopher; Aug 23: A Letter from Nikola Tesla by Ben Lillie; Aug 24: Peering Into the Future- The Decadal Survey by Mike Simonsen; Aug 25: Can I Look Through Your Telescope? by Rob Berthiaume.

This week the shows include: Aug 12: Kepler Keeps on Giving by Ball Aerospace; Aug 13: Bringing Children to Mercury by Bob Hirshon, AAAS; Aug 14: Amazing Water! by Todd Gonzales; Aug 15: Mars in August by Carolyn Collins Petersen; Aug 16: How to Get Kids Interested in Science by Zachary and Richard Kessin; Aug 17: Are We Made of Stardust? by Stuart Clark; Aug 18: Lunar Dust and Dreams by The NASA Lunar Science Institute.

This week the shows include: Aug 05: The Soul of Astronomy by Brendan Casey ; Aug 06: Expanding Horizons by Bill Hudson of 2012 Hoax ; Aug 07: Aurora and Solar Coronal Mass Ejections by Slacker Astronomy; Aug 08: How to Successfully Chase a Solar Eclipse by Edgardo Molina ; Aug 09: Fascination Astronomy by The Hidden Space Project ; Aug 10: Astronomy for Non - human Life Forms by Steve Nerlich & The Ordinary Guy ; Aug 11: Encore Podcast : The Brightest Stars In The Sky by The American Association of Variable Star Observers.

This week the shows include: Jul 29: Astronomy and iPad by Tecnocasters by The Tecnocasters; Jul 30: A Brief Introduction to Galaxy Dynamics by Edgardo Molina; Jul 31: Space Medicine by Mick Vagg; Aug 01: Discussing the issues of Knowledge through Astronomy by Manoharan Karthigasu; Aug 02: Solar System Nomenclature by Brian Gray; Aug 03: A Friends' Salute to the Blue Collar Scientist, Jeff Medkeff by Mark DeVito and Friends; Aug 04: Red Light and Night Vision by Alice Enevoldsen.

This week the shows include: Jul 22: On Being a Black Hole by Steve Nerlich, with Graham Nerlich; Jul 23: Interesting Moons of our Solar System by Bollix!; Jul 24: A Gargantuan Infrared Telescope Project for Mexico by Edgardo Molina by Edgardo Molina; Jul 25: Galileo -- Eclipse Chaser? by Mark Thompson; Jul 26: Another demotion for Pluto? Or is it about to become King of the Dwarfs? Part 2 by Marc West; Jul 27: Interesting Comets by Ted Judah; Jul 28: Origins of the Moon by The NASA Lunar Science Institute.

This week the shows include: Jul 15: Black Holes & more Megamasers! by Richard Drumm; Jul 16: Your Head is Jupiter by Sandy Antunes; Jul 17: What Were the First Celestial Objects by Stuart Clark; Jul 18: Lunar Forum 2010 Preview by NLSI by The NASA Lunar Science Institute; Jul 19: Where Do We Come From? by Carolyn Collins Petersen; Jul 20: Spelling Her Way into Space by Elizabeth Howell; Jul 21: One and a Half Percent by Ben Lillie.

This week the shows include: Jul 08: Eta Carinae and Supernova Imposters by Slacker Astronomy; Jul 09: A Champion at Keeping Cool by Bob Hirshon, AAAS; Jul 10: Total Solar Eclipse in Easter Island by Jay Pasachoff; Jul 11: A Zoo of Active Galaxies by Chris Lintott and Kevin Schawinski; Jul 12: Disney, Dr. Seuss and the World of Astronomy by Michelle Meyer, Jacqueline Dennis, and Micol Christopher; Jul 13: Dr. Lucas Macri on the Extragalactic Distance Scale by Slacker Astronomy; Jul 14: Project CLEA by Sue Ann Heatherly, of NRAO.

This week the shows include: Jul 01: Tachyons by Craig Robertson; Jul 02: How to Enjoy a Meteor Shower by AstronomyCast; Jul 03: The Legacy of Paris Pismis by Edgardo Molina; Jul 04: Astronomy in Colonial America by Alvin Ashworth; Jul 05: Another demotion for Pluto? Or is it about to become King of the Dwarfs? Part 1 by Marc West; Jul 06: What Goes Up, Must Come Down (Most Times)! by Patrick McQuillan; Jul 07: A 365 Days Classic: Will the World End in 2010? by Cameron Hummels.

This week the shows include: Jun 24: Observing Between the Ground and Orbit by Rob Berthiaume; Jun 25: Mysterious Magnetar XTE J1810-197 by Sue Ann Heatherly, of NRAO; Jun 26: Dark Matter: Not Like the Luminiferous Ether by Rob Knop; Jun 27: My Favorite Space Shuttle Missions by Steve Nerlich and Nancy Atkinson; Jun 28: Is There Life on Titan? by Adam Fuller; Jun 29: The Adler Planetarium Sky Theater at 80 by The Adler Planetarium; Jun 30: Wet Mars by The Tecnocasters.

This week the shows include: Jun 17: How Did the Universe Form? by Stuart Clark; Jun 18: A Spaceport of Her Own by Dr. Alex (Sandy) Antunes; Jun 19: Second Place Vesta by Brains Matter; Jun 20: The June Solstice: The Week the Sun Stood Still by Judith Young; Jun 21: Diane Duane by Diane Duane; Jun 22: Pictures of Science by Ben Lillie; Jun 23: Pickering's Women by Mike Simonsen.

This week the shows include: Jun 10: Hayabusa by Steve Nerlich; Jun 11: Spirit Won?t Give Up The Ghost by Bob Hirshon, AAAS; Jun 12: The Great Millimeter Telescope at Sierra Negra in Mexico by Edgardo Molina; Jun 13: Matariki Rising by Ron Fisher; Jun 14: Astropoetry and Literature by Carolyn Collins Petersen; Jun 15: The "Little Lark" that Propelled Canada into the Space Age by Elizabeth Howell; Jun 16: Education, Illiteracy, and Hoaxes, Oh My! by Emily Temple-Wood.

This week the shows include: Jun 03: Mysterious Moon Rocks by The NASA Lunar Science Institute; Jun 04: Starrytelling at Alice Deal Middle School by Giraffe 'n Ant Productions; Jun 05: The Unknown Face of Baja: High-End Astronomy by Edgardo Molina; Jun 06: Thinking Outside the Box by Bill Hudson of 2012 Hoax; Jun 07: Dark Skies, Bright Kids by Nicole Gugliucci; Jun 08: AAVSONet by Slacker Astronomy; Jun 09: NASA Finds NEEMO by Nancy Atkinson.

This week the shows include: May 27: Famous Physicians in Astronomy by Mick Vagg; May 28: Watch This Space by Steve Nerlich; May 29: What's In a Name? The Story of Parsecs by Olaf Davis; May 30: Astronomy on Twitter by The Tecnocasters; May 31: The 75th Anniversary of the David Dunlap Observatory by The Royal Astronomocial Society of Canada; Jun 01: 35 Years Under the Stars by Bob Moler; Jun 02: The Journey of Astronomy by Megan Argo.

This week the shows include: May 20: Going Hollywood by Sandy Antunes; May 21: Common Questions and Answers by RapidEye; May 22: Carl Sagan by Craig Robertson; May 23: Were the fundamental constants of physics different in the early Universe? by Rob Knop; May 24: A Mexican Name on the Moon by Edgardo Molina; May 25: Hypervelocity Stars by Brains Matter; May 26: StarryTelling from Takoma Park Middle School by Giraffe 'n Ant Productions.

This week the shows include: May 13: The Square Kilometre Array by the SKA Outreach Team; May 14: Next Generation Space Materials by Bob Hirshon, AAAS; May 15: Griffith Birthday by Carolyn Collins Petersen; May 16: Thermostat by Ben Lillie; May 17: What are Black Holes? by Stuart Clark; May 18: Our Place in Space by Pamela Gay; May 19: It's a Zoo Out There On the Moon! by The NASA Lunar Science Institute.

This week the shows include: May 06: Warp Drive Part 2 by Renata and Damian Handzy; May 07: Citizen Sky by Slacker Astronomy; May 08: How Lunar Cycles Affect Wildlife by Wild Ideas; May 09: Up Close with the Eyjafjallajokull Volcano by Col Maybury and Snaevarr Gudmundsson; May 10: The Late Heavy Bombardment -- was it real? by Emily Lakdawalla; May 11: Speculative Fiction: How The Russians landed on the Moon by C. Augusto Valdés; May 12: Reach for the stars: Advice on a career in astrophysics by Renee Hlozek and Sarah Miller.

This week the shows include: Apr 29: Water on the Moon! by The NASA Lunar Science Institute; Apr 30: Astrotips by The Tecnocasters; May 01: Noche de las Estrellas, Mexico's Nationwide Star Party by Edgardo Molina; May 02: Astronomy in your Pocket: Astronomy Apps for iPhone by Mark DeVito; May 03: Hippocrates meets Hipparchus by Mike Vagg; May 04: Lapetus and the Cassini Regio by Alice Enevoldsen; May 05: The Continuing Copernican Revolution by Rob Knop.

This week the shows include: Apr 22: A Space Journalist's Big Adventure by Col Maybury; Apr 23: Location, Location, Location! by Sue Ann Heatherly, of NRAO; Apr 24: Ophiuchus- the 13th Sign of the Zodiac by Mike Simonsen; Apr 25: The Moon-Our Sidekick by Rob Berthiaume; Apr 26: Mariners, Cancer and Bombs by Ben Lillie; Apr 27: The Green Flash by Rob Sparks; Apr 28: StarryTelling (TM) at the British School of Washington by The British School of Washington.

This week the shows include: Apr 15: Creativity and Astronomy by Tatiana Ouvarova; Apr 16: Building Your Career in Astronomy by AstronomyCast; Apr 17: Was Einstein Right? by Stuart Clark; Apr 18: Uranus: Not Just the Butt of Jokes by Emily Temple-Wood; Apr 19: Starry-Telling at Parkland Middle School by Elizabeth Wallace; Apr 20: Megamasers by Richard Drumm; Apr 21: Sudden Ionospheric Disturbances by Jim Stratigos.

This week the shows include: Apr 08: Making the VASIMR Engine by Sawyer Rosenstein and Montserrat Cordero; Apr 09: NASA’s Basement Tapes by Bob Hirshon, AAAS; Apr 10: Introduction to Practical Astronomy by Justin Clayden; Apr 11: Celestial Coordinates by Mark DeVito; Apr 12: A Planetary Defense System by Steve Nerlich; Apr 13: The Rescue of Apollo 13, with NASA Engineer Jerry Woodfill by Nancy Atkinson; Apr 14: What is Astronomy? by Carolyn Collins Petersen.

This week the shows include: Apr 01: BREAKING NEWS! Pluto Regains Planet Status! by Patrick McQuillan; Apr 02: Richard Emmons by Brian Gray; Apr 03: Interview with Robert Naeye of Sky & Telescope, Part 2 by Slacker Astronomy; Apr 04: Introduction to the Theory and Practice of Jovian Radio Astronomy by Edgardo Molina; Apr 05: Sightings: Seth Shostak and SETI by Ted Judah; Apr 06: Cosmology and Creation - Many Stories, Many Skies At Perth's Gravity Discovery Centre by Kylie Sturgess; Apr 07: Wooden Satellites by Sandy Antunes.

This week the shows include: Mar 25: The Mirrors that Make James Webb by Roz Brown/Ball Aerospace; Mar 26: Whence Supernovae by Rob Knop; Mar 27: A Scale Model of the Universe by Rob Wolfram; Mar 28: How Long Can the International Space Station Operate? by Nancy Atkinson; Mar 29: Dr. Debunko by The Adler Planetarium; Mar 30: Fred Hoyle by Craig Robertson; Mar 31: Dr. Who and the Silver Spiral by Megan Argo.

This week the shows include: Mar 18: Father and Son at the Eyepiece by Edward Gomez; Mar 19: Why Go to the Zoo? by Dr. Alex (Sandy) Antunes; Mar 20: The March Equinox: International Unity Day by Judith Young; Mar 21: Dark Skies Crusader Sheds Light on Light Pollution by Constance Walker; Mar 22: Detecting Moons Around Extrasolar Planets by Adam Fuller; Mar 23: What Can the Dark Matter Be? by Steve Nerlich; Mar 24: Broken Teeth and the Fate of the Universe by Ben Lillie.

This week the shows include: Mar 11: Go on a Spacewalk with Astronaut Chris Hadfield by Nancy Atkinson; Mar 12: The Hunt for Vulcanoids by Bob Hirshon, AAAS; Mar 13: I "Heart" Hartley 2! by Elizabeth Warner; Mar 14: A Guide to the Stars and Planets by Carolyn Collins Petersen; Mar 15: Julius Caesar and Calendar Reform by Zachary Kessin and Julia Smith; Mar 16: Scouting Merit Badge by Damian Handzy; Mar 17: Why Do the Planets Stay in Orbit? by Stuart Clark.

This week the shows include: Mar 04: Dinosaurs and Asteroids by Damian and Sofia Handzy; Mar 05: A Conversation with George Diller of NASA TV by Nancy Atkinson; Mar 06: What to do in case of a total solar eclipse and an overcast sky: Mexico City 1991 by Edgardo Molina; Mar 07: Interview with Robert Naeye, Editor-in-Chief of Sky & Telescope by Slacker Astronomy; Mar 08: The Folklore Surrounding the Aurora by Craig Robertson; Mar 09: Adaptive Optics Saves Earth by Rob Sparks; Mar 10: 2012: The Profits of Doom by Bill Hudson.

This week the shows include: Feb 25: Where's the Best Place for the Biggest Telescopes? by Robert Berthiaume; Feb 26: Playing Hide and Seek with a Binary Pulsar by Sue Ann Heatherly, of NRAO; Feb 27: Ceres: Dwarf Planet or Very Big Asteroid? by Steve Nerlich; Feb 28: The Universe in 15 Minutes by The Tecnocasters; Mar 01: Our Nearest Variable Star by Mike Simonsen; Mar 02: The Parkes Dish by Eran Segev; Mar 03: A 6 Year Old's Question on Star Quakes by Brains Matter.

The 7 days of 365 Days of Astronomy for week 60. This week the shows include:  Feb 18: The Discovery of Pluto by Ted Haulley; Feb 19: 4 Astronomers on Why They Do It by Sandy Antunes; Feb 20: Mars and the Red Stars by Tavi Greiner; Feb 21: An Introduction to Active Galactic Nuclei by Olaf Davis & Renee Hlozek; Feb 22: Jonathan McDowell Visits Thayer Academy by Jamie Formato; Feb 23: Where IS the Center of the Universe? by Rob Knop; Feb 24: Sidewalk Astronomy by Jay Horowitz.

This week the shows include: Feb 11: Nature's Most Precise Clocks May Make 'Galactic GPS' Possible by Kevin John and Paul Ray; Feb 12: 41st Lunar and Planetary Science Conference Preview by Bob Hirshon, AAAS; Feb 13: BLAST! by Nancy Atkinson; Feb 14: Look For Me Up There by Carolyn Collins Petersen; Feb 15: The First Astronomers by Brains Matter; Feb 16: How Did the Earth Form? by Stuart Clark; Feb 17: 80th Anniversary of the Paragould Meteorite by Ken Renshaw.

This week the shows include: Feb 04: Spectroscopy 101 by Richard Drumm; Feb 05: Getting Started in Astronomy: Then and Now by David Chapman and Andrew Misner; Feb 06: Expanding an Already Very Large Array by Nicole Gugliucci; Feb 07: Retro Science: Determining the Eccentricity of the Moon's Orbit by Slacker Astronomy; Feb 08: The Supernova that Bounces by Rob Bowman; Feb 09: Things That Go Bump in the Night by Patrick McQuillan; Feb 10: Astronomical Lessons for Life by Mark Jones.

This week the shows include: Jan 28: A Series of Spectacular Events by Colm Ryan; Jan 29: The Dreamtime Meteor Crater by Steve Nerlich, with Duane Hamacher; Jan 30: The Universe in 10 Minutes by The Tecnocasters; Jan 31: 2012: The Impact by Bill Hudson; Feb 01: Migration by Celestial Navigation by Wild Ideas; Feb 02: Amateur Astronomy's Affliction: Aperture Fever by RapidEye; Feb 03: The GLOBE at Night Campaign: Our Light or Starlight? by Connie Walker.

This week the shows include:  Jan 21 Ilgarijiri: Aboriginal Art Meets Modern Astronomy by Megan Argo; Jan 22 Black Holes and the Formation of Galaxies by Rob Knop; Jan 23 A Brief Biography of George Gamov by Craig Robertson; Jan 24 Friedrich Wilhelm August Argelander by Mike Simonsen; Jan 25 6th Anniversary of Opportunity's Arrival on Mars by Ken Brandt; Jan 26 Once Upon a Lonely Sun by Pamela Gay; Jan 27: Earth Clones by Chris Impey.

This week the shows include: Jan 14 You Can Do Astronomy by Carolyn Collins Petersen; Jan 15 Go Higher or Go to Antarctica by Alex (Sandy) Antunes; Jan 16 Sidewalk Astronomy by Daniel Elbert Herron; Jan 17 What is the Universe? by Stuart Clark; Jan 18 Arming Yourself for Battle by Bill Hudson of 2012 Hoax; Jan 19 Film Astrophotography by Zachary Kessin; Jan 20 The Celestial Police by Brian Gray.

The 7 days of 365 Days of Astronomy for week 54. This week the shows include: Jan 07: Are You Sure Those are Moons by Jove? by Mark Thompson. Jan 08: Lakes on Mars by Bob Hirshon, AAAS. Jan 09: Warp Drive by Renata and Damian Handzy. Jan 10: Annular Eclipse in India by Jay Pasachoff. Jan 11: The New Solar System by Andy Briggs. Jan 12: Climbing the Distance Ladder by Christian Ready. Jan 13: Remembering the Atwood Sphere by Elizabeth Fracek.

The 7 days of 365 Days of Astronomy for week 53. This week the shows include: Dec 31: The IYA New Media Working Group Bids 2009 Adieu! by IYA New Media Working Group. Jan 01: One Final Look Back at 2009 by Pamela Gay. Jan 02: Water on the Moon by Nancy Atkinson. Jan 03: Kepler and Extrasolar Asteroids by Slacker Astronomy. Jan 04: Dark Days of Winter by Alice Enevoldsen. Jan 05: How Far is Far? by Steve Nerlich. Jan 06: Fighting the 2012 Hoax by Bill Hudson.

The 7 days of 365 Days of Astronomy for week 52 2009. This week the shows include: Dec 24: Dancing in the Dark: Deities, Celebrations, and the Bottom of the Year by Diane Duane. Dec 25: Star of Wonder by The Adler Planetarium. Dec 26: Confessions of a Christmas Trash Scope by Richard S. Wright. Dec 27: The Protestant Galileo by Ted Haulley. Dec 28: Life in Technicolor by Maria Pereira from Columbia Astronomy. Dec 29: Decoding Lapetus: An Exercise in "Sybil" Engineering by Kevin Grazier. Dec 30: Skylights 2010 by Patrick McQuillan.

The 7 days of 365 Days of Astronomy for week 51 2009. This week the shows include: Dec 17: An Interview with Johannes Kepler by John McFarland and Thomas Covington. Dec 18: Galaxy Formation by Steve Nerlich, with Dr. Pamela Gay. Dec 19: Lurking ULIRGs by Sue Ann Heatherly. Dec 20: Carl Sagan and the Interstellar Adventures of the Voyager Mission by Dr. Amanda Bauer. Dec 21: December Solstice: Celebrating the Light by Judith Young. Dec 22: A Tribute to Carl Sagan by Carolyn Collins Petersen. Dec 23: See the Universe with Chromoscope by Nancy Atkinson.

The 7 days of 365 Days of Astronomy for week 50 2009. This week the shows include: Dec 10: Blue Star Blues by Mel Blake, Ashley Wills and Cara Depew. Dec 11: Returning to the Moon? Too Soon? by Larry Sessions. Dec 12: Heat by Slacker Astronomy. Dec 13: Infrared Instrumentation and the Large Binocular Telescope by Richard B. Drumm. Dec 14: Tycho Brahe by John McFarland of the Johannes Kepler Project. Dec 15: Anomalies by Steve Nerlich. Dec 16: A Tribute to Sir Arthur C Clarke by The Sri Lanka Astronomical Association.

The 7 days of 365 Days of Astronomy for week 49 2009. This week the shows include: Dec 03: When the Universe Was Young by Richard B. Drumm. Dec 04: The WISE Mission by Ball Aerospace & Technologies Corp.. Dec 05: Galileo and the Moons of Jupiter by Emily Lakdawalla. Dec 06: The Celestial Alignment of 2012 by Chuck Bueter. Dec 07: Don't Lick the Telescope, and Other Tips for Cold-Weather Observing by Mike Simonsen. Dec 08: What is the Kuiper Belt? by Susan, Amanda & Kevin Murph. Dec 09: Teaching Science in Schools by Manoharan Karthigasu.

The 7 days of 365 Days of Astronomy for week 48 2009. This week the shows include: Nov 26: The LSST & You – a New Way to Observe! by Suzanne Jacoby and assorted LSST Project Members. Nov 27: Channeling Galileo by Mark Thompson. Nov 28: An Armchair Tour of the Universe in 10 Minutes by Rob Bowmar. Nov 29: The Astronomy of Shakespeare by Dr. Leslie Peterson and Dr. Mel Blake. Nov 30: What Galileo Discovered at Jupiter by Adam Fuller from Columbia Astronomy. Dec 01: Oh Be A Fine Girl, Kiss Me by Chris Marr. Dec 02: Dr. Fred Watson: Australian Stargazer by Kylie Sturgess.

The 7 days of 365 Days of Astronomy for week 47 2009. This week the shows include: Nov 19: A Ceremony Celebrating Dark Skies by Scott Kardel. Nov 20: MUSTANG Gallops Towards Clusters Last Stand by Sue Ann Heatherly. Nov 21: Under a New Sky by David Ault. Nov 22: Go Up and Turn Right by Steve Nerlich. Nov 23: The Extraterrestrials in Your Back Yard by Lia Corrales from Columbia Astronomy. Nov 24: On the Screen: Science Fact vs. Science Fiction by Jane Platt and Kevin Grazier. Nov 25: The Case of the Lobate Scarps by Carolyn Collins Petersen.

The 7 days of 365 Days of Astronomy for week 46 2009. This week the shows include: Nov 12: Cassini/Huygens: Rewriting the Textbook on Saturn by Kevin Grazier. Nov 13: Thrilling Meteors Streak the Sky by Gregg Paris of the San Diego Astronomy Association. Nov 14: Rabbit on the Moon by Harith, Rahul, and Rohith. Nov 15: The Royal Family of Astronomy by Ted Haulley. Nov 16: Carolyn Herschel's White Rose - NGC 7789 by RapidEye Observatory. Nov 17: Astronomy Without an Astrophysics Degree by AstronomyCast. Nov 18: Astrophilia in the City That Never Sleeps by Ian Cheney.

The 7 days of 365 Days of Astronomy for week 45 2009. This week the shows include: Nov 05: Earth and Sky: Together at Last! Pt. 2 by Alan Perkins. Nov 06: SOFIA – Flight Tests and the Promise of New Science by Martin Ratcliffe. Nov 07: Bright Bolide by Slacker Astronomy. Nov 08: Radio Astronomy: An Important Tool by Nitza Santiago from Columbia Astronomy. Nov 09: Celebrate Carl Sagans 75th Brithday with Longtime Collaborator Ann Druyan by Mat Kaplan. Nov 10: Wake Up and Smell the Baloney! by Larry Sessions. Nov 11: An Amateur Goes Pro. Almost. by Slacker Astronomy.

The 7 days of 365 Days of Astronomy for week 44 2009. This week the shows include: Oct 29: The Deep Space Network by Steve Nerlich. Oct 30: Sky and Earth: Together at Last! Pt. 1 by Alan Perkins. Oct 31: The Fermi Paradox and the Drake Equation by Al Ashworth. Nov 01: Listening to Gravitational Waves: A New Window on the Universe by Gareth Jones. Nov 02: Cassini's Deepest Plume Passage: The "E7" Flyby of Enceladus" by Anne Verbiscer. Nov 03: WISE: Mapping the Sky in Infrared Light by Bryan Mendez. Nov 04: Top Ten Ways to Get Kids Excited About Astronomy! by Damian Handzy.

The 7 days of 365 Days of Astronomy for week 43 2009. This week the shows include: Oct 22: The Armchair Universe by Carolyn Collins Petersen. Oct 23: A History of Modern Astronomy in Thailand, pt. 2 by Visanu Euarchukiati. Oct 24: Great Light Switchout by The International Dark-Sky Association. Oct 25: The TDRS System by Steve Nerlich. Oct 26: Hot Tub Astronomy by Gary Santoro. Oct 27: A Life in Astronomy by Richard Saunders of Skeptic Zone. Oct 28: Funny You Should Ask About the Next Step in Your Astronomy Journey by Jeff Thibodeau.

The 7 days of 365 Days of Astronomy for week 42 2009. This week the shows include: Oct 15: The Jewish Calendar, or "When is Passover this Year Anyway?" by Zachary Kessin and Rabbi Hillel Mazels. Oct 16: Our Growing Galaxy by Sue Ann Heatherly. Oct 17: The Search for WIMPs by Jimmy Erickson. Oct 18: Geometry Vs. Lunacy by Mark Thompson. Oct 19: When Galileo Fell Into Jupiter by Adam Fuller from Columbia Astronomy. Oct 20: Mercury: Close Encounter for the Third Time by Bob Hirshon. Oct 21: 125 Years of the Prime Meridian at Greenwich by Marek Kukula of the Royal Observatory, Greenwich.

The 7 days of 365 Days of Astronomy for week 41 2009. This week the shows include:Oct 08: Learning About Seasons in a Planetarium by Chuck Dibbs and Virginia Beach City Public Schools. Oct 09: The Search for Distant Worlds by Christopher Crockett. Oct 10: I Know Why It's Dark at Night. Do You? by Terry Johnson and Friends. Oct 11: Quiet Skies by Sue Ann Heatherly. Oct 12: Lovell Telescope by Stuart Lowe and Tim O'Brien. Oct 13: The Summer We Flew to the Moon by Mike Simonsen. Oct 14: A WISE mission to Study Asteroids and Other Objects by Jane Platt.

The 7 days of 365 Days of Astronomy for week 40 2009. This week the shows include: Oct 01: My Favorite Things? Getting Astronomy on Your Children’s Favorites List by Patrick McQuillan with help from Connor and Ryan McQuillan. Oct 02: Moon Town - Scifi in Web Comics by Paul  Caggegi of The Process Diary. Oct 03: Red Fireballs, Quiet Quakes and Heat Haze by Society for Popular Astronomy. Oct 04: Measuring Time by Nik Whitehead. Oct 05: Postcards from the Universe by Sky at Night Magazine. Oct 06: Crashing to Ground: Anniversary of the Impact of 2008 TC3 by Emily Lakdawalla. Oct 07: Mira and the Pulsating Red Giants by The American Association of Variable Star Observers.

The 7 days of 365 Days of Astronomy for week 39 2009. This week the shows include:Sep 24: Faces of the Moon by Bob Crelin. Sep 25: Modern Telescopes and Observation Techniques by The Adler Planetarium. Sep 26: The IAU Strategy by Carolina Ödman. Sep 27: The Phobos LIFE Experiment by Mat Kaplan and Bruce Betts. Sep 28: The Connection between Metal Abundances and the Evolution of Galaxies by Duane Lee from Columbia Astronomy. Sep 29: Space Law by Harold Goldner. Sep 30: The Delight of Stars by Brother Guy Consolmagno.

The 7 days of 365 Days of Astronomy for week 38 2009. This week the shows include: Sep 17: Top Ten Telescope Mistakes for Beginners by Robin Scagell.Sep 18: Pulsar Search Collaboratory by Sue Ann Heatherly. Sep 19: Ed White's Glove by Steve Nerlich. Sep 20: September Equinox: International Unity Day by Judith Young. Sep 21: Notes from a Parking Lot by Rob Simbeck. Sep 22: The First Female Radio Astronomer by Brains Matter. Sep 23: Looking for a Reason. Why Astronomy? by Richard Saunders of Skeptic Zone.

The 7 days of 365 Days of Astronomy for week 37 2009. This week the shows include:Sep 10: Singing the Ultraviolet Blues by Carolyn Collins Petersen. Sep 11: Pluto, Stand Thou Still! by Larry Sessions. Sep 12: Slacker Astronomy Interview with George Hrab by Slacker Astronomy. Sep 13: Why We See the Same Side of the Moon by Gordon Houston. Sep 14: The Starry Night by Sayward Duffano. Sep 15: Interview with Star Trek's Tim Russ by Ed Sunder. Sep 16: Epo's Chronicles by Kamal S. Prasad, Tiffany Schwab, Kevin John and Logan Hill.

The 7 days of 365 Days of Astronomy for week 36 2009. This week the shows include:Sep 03: Gravitational Lensing by SkyLK. Sep 04: Saturn's Rings Do a Disappearing Trick by Emily Lakdawalla. Sep 05: A-Hunting We Will Go! by John Troeltzsch & Roz Brown. Sep 06: Eyes Above: The Emotions of a Scientific Discovery by The Astronomical Observatory of the Autonomous Region of the Aosta Valley (OAVdA). Sep 07: Cataclysmic Variables by The American Association of Variable Star Observers. Sep 08: Who Wants to Be an Astronomaire? by Wayne Harris-Wyrick. Sep 09: Planet Searching at the Gemini Observatory by The Gemini Observatory.

The 7 days of 365 Days of Astronomy for week 35 2009. This week the shows include:Aug 27: Need a Unique Birthday Gift? “Buy” a Birthday Star by Patrick and Ryan McQuillan. Aug 28: Saturn’s Moon Enceladus – Past, Present, and Future by David Seal. Aug 29: My Life with Charlie by David Powell. Aug 30: The Environments of Jupiter's Moons by Amy Bowen. Aug 31: Grote Reber: The First Radio Astronomer by Destry Saul of Columbia Astronomy. Sep 01: Re-Discovering the Wonderment of the Night Sky by Mike DeVito. Sep 02: STEREO-IMPACT: Our UN-quiet Sun by UC Berkeley's Center for Science Education.

The 7 days of 365 Days of Astronomy for week 34 2009. This week the shows include: Aug 20: Walking With Planets by Andy Brigg. Aug 21: Flying Around the Solar System by Nancy Atkinson. Aug 22: Astronomy for Beginners by Assi Süer. Aug 23: Galileo Presents a Telescope to the Venetian Senate by Mark Thompson. Aug 24: The Reemergence of Planetary Science: Revisiting Percival Lowell by Holly Larson from Columbia Astronomy. Aug 25: The Scenery of the Night by The U.S. National Park Service. Aug 26: 20th Anniversary of Voyager 2 at Neptune by Martin Ratcliffe and Dr. Ed Stone.

The 7 days of 365 Days of Astronomy for week 33 2009. This week the shows include:Aug 13: Down to My Last Quarter by Larry Sessions. Aug 14: The Cosmos from the Outback by Carolyn Collins Petersen. Aug 15: Chaucer's Astronomy & Treatise on the Astrolabe by Dave Wilton. Aug 16: An African Boy's Heavenly Dream by Abraham Samma. Aug 17: Let There Be Night by Chuck Bueter. Aug 18: Helium and the Sun by Susan and Amanda Murph. Aug 19: What Slammed Into Jupiter? by SkyGuy.

The 7 days of 365 Days of Astronomy for week 32 2009. This week the shows include: Aug 06: UNAWE: Experiences With Children by Universe Awareness. Aug 07: Eclipsing Binaries by The American Association of Variable Star Observers. Aug 08: A History of Modern Astronomy in Thailand by Visanu Euarchukiati. Aug 09: Perseids Meteor Shower by Christopher Crockett. Aug 10: What Happened to Saturn's Rings? by Adam Fuller from Columbia Astronomy. Aug 11: Cassini Watches the Sun Rise Above Saturn's Rings by Emily Lakdawalla. Aug 12: Ancient Astronomy: The Mayans by Augusto Valdés.

The 7 days of 365 Days of Astronomy for week 31 2009. This week the shows include: Jul 30: A Tour Through the Lives of the Stars by André Gonçalves. Jul 31: Now Tweet This: Reaching Beyond Mainstream Media by Rob Keown and Tavi Greiner. Aug 01: How I Got Into Astronomy by Robert Simpson of Orbiting Frog. Aug 02: Stardust@home: the Search for Interstellar Dust by Dr. Andrew Westphal and Anna Butterworth. Aug 03: Black Hole Street Smarts by Lia Corrales and David Tam of Columbia University Astronomy. Aug 04: Aliens in Roswell by Brian Dunning. Aug 05: What Do We See When We Look Up? by Oklahoma City Astronomy Club.

The 7 days of 365 Days of Astronomy for week 30 2009. This week the shows include:Jul 23: Everything Old is New Again by Ball Aerospace & Technologies Corp.Jul 24: Astronomical Arts and Crafts for Kids by Amy Bowen. Jul 25: The Southern Cross by Steve Nerlich. Jul 26: Gravity Wave Astronomy by Ivan Semeniuk. Jul 27: Astronomical Ballooning - Or, What Goes Up Must Come Down by Sarah Tuttle. Jul 28: Opening Up the Sky to Kids by Jeff Wood. Jul 29: Why Should We Teach Astronomy in High Schools? by Colin Jagoe.

The 7 days of 365 Days of Astronomy for week 29 2009. This week the shows include: Jul 16: The July 22 Total Solar Eclipse by Jay Pasachoff. Jul 17: The Lucifer Project by Brian Dunning. Jul 18: The Solar Eclipse of 1963 and Other Reminiscences by Peter Sosna. Jul 19: Ray Bradbury Looks Back at Apollo 11 by Mat Kaplan. Jul 20: The Eagle Has Landed by Ted Haulley. Jul 21: Moonstruck by David Kurtz. Jul 22: Astronomy in Anglo-Saxon England by Dave Wilton.

The 7 days of 365 Days of Astronomy for week 28 2009. This week the shows include: Jul 09: Measuring the Black Hole by Carolyn Collins Petersen. Jul 10: How Amazingly Unlikely is Your Birth? by Larry Sessions. Jul 11: Apollo 11 Through the Eyes of a Young Girl by Nancy Atkinson. Jul 12: Women on the Moon by Mark Tillotson. Jul 13: Windy City Astronomy by Elizabeth Fracek. Jul 14: Telescope 400 by Robin Scagell. Jul 15: Your Local Astronomy Club by Ed Sunder.

The 7 days of 365 Days of Astronomy for week 27 2009. This week the shows include: * Jul 02: Herschel and Planck Set Sail into the Cold Universe by Edward and Haley Gomez. * Jul 03: Universe Awareness: Children's Voices by Carolina Ödman. * Jul 04: New World Ordered by Daniel Raffaele. * Jul 05: Looking Towards the Center of the Galaxy by Christopher Crockett. * Jul 06: Science and Religion by Gurbir Singh. * Jul 07: The Mysterious Epsilon Aurigae by The American Association of Variable Star Observers. * Jul 08: Archimede’s Death Ray and Dante’s Inferno: The Real Story of How Galileo Ignited the Age of the Telescope by Mark Thompson.

The 7 days of 365 Days of Astronomy for week 26 2009. This week the shows include: * Jun 25: Galileo's Telescope by The Adler Planetarium. * Jun 26: The Palomar Transient Factor by Scott Kardel. * Jun 27: The Cosmic Microwave Background by Richard B. Drumm. * Jun 28: Space Travel in Science Fiction by Vance Weaver. * Jun 29: 365 Days of Astronomy Podcast Update by IYA New Media Working Group. * Jun 30: It's All About the Reference Frames by Kenneth Johnston. * Jul 01: S.K.A. Music - The Square Kilometer Array by Kylie Sturgess.

The 7 days of 365 Days of Astronomy for week 25 2009. This week the shows include: * Jun 18: THEMIS/Artemis by APF. * Jun 19: A Modest Black Hole by Sue Ann Heatherly. * Jun 20: Magnetar the Magnificent by Carolyn Collins Petersen. * Jun 21: The June Solstice: The Week the Sun Stood Still by Judith Young. * Jun 22: Galileo and His Lute by Mark Thompson. * Jun 23: Star Parties: Fun in the Dark by Ted Judah. * Jun 24: Telescopes for Schools by Society for Popular Astronomy.

The 7 days of 365 Days of Astronomy for week 24 2009. This week the shows include: * Jun 11: Round, Round, Round We Go by Larry Sessions. * Jun 12: Does Dark Matter Really Exist? by Jim Stratigos. * Jun 13: Tycho Brahe’s Nose by James Clifton. * Jun 14: The Mars Global Surveyor by Nancy Atkinson. * Jun 15: Displaying Saturn by Marek Kukula of the Royal Observatory, Greenwich. * Jun 16: International Dark Sky Parks & Reserves – Just in Time for Summer Vacation! by The International Dark-Sky Association. * Jun 17: The Big Bang! by Josh Schroeder of Columbia Astronomy.

The 7 days of 365 Days of Astronomy for week 23 2009. This week the shows include: * Jun 04: JPL's Greatest Hits by Bruce Irving. * Jun 05: Beginner's Guide to Observing Jupiter by Martin Ratcliffe. * Jun 06: Backyard Astrophotography - A Visual Effects Artist's Escape to Reality by The Process Diary. * Jun 07: The Brightest Stars in the Sky by The American Association of Variable Star Observers. * Jun 08: The Universe in Ultraviolet! by Erika Hamden of Columbia Astronomy. * Jun 09: Who Was Edwin Hubble? by Doug Allen. * Jun 10: The Face on Mars by Brian Dunning.

The 7 days of 365 Days of Astronomy for week 22 2009. This week the shows include: * May 28: The Search for Other Habitable Worlds by Geoff Marcy. * May 29: Dear Lyla, This is Where You Came From by John Noble. * May 30: The Power of the Force! (Astrology Part 2) by Patrick McQuillan. * May 31: Stars that Fell Like Rain by John Johnson. * Jun 01: Supernovae by Maureen Teyssier of Columbia Astronomy. * Jun 02: Sky Above and Worlds Beyond: A Book Review and Memoir by Amy Bowen. * Jun 03: Why We Need Neutrino Telescopes by Steve Nerlich.

The 7 days of 365 Days of Astronomy for week 21 2009. This week the shows include: * May 21: Hanny's Voorwerp and the Galaxy Zoo by Ted Judah. * May 22: Mars Exploration: A Quick History by Susan and Amanda Murph. * May 23: A Cheap "Name a Star" Gift for Graduates by Bruce Palmquist. * May 24: We're Expanding - and Accelerating! by Brains Matter. * May 25: Tides: More Than What Floats Your Boat by Robert Morehead from Columbia Astronomy. * May 26: Astronomer George Ellery Hale by Scott Kardel. * May 27: Smiley, the Little Dish that Could by Christi Whitworth.

The 7 days of 365 Days of Astronomy for week 20 2009. This week the shows include: * May 14: A Tour of Sydney Observatory by The Skeptic Zone Podcast. * May 15: Giant Pulses in the Crab by Sue Ann Heatherly. * May 16: Back to the Dark Ages: Responsible Nighttime Lighting by Connie Walker and Rob Sparks. * May 17: Citizen Scientists - Making a Difference and Having Fun by Tavi Greiner and Rob Keown. * May 18: Life of a Proton by Nik Whitehead. * May 19: When Did Galileo Really Learn About the Telescope? by Mark Thompson. * May 20: The Missing Cosmonauts by Brian Dunning.

The 7 days of 365 Days of Astronomy for week 19 2009. This week the shows include: * May 07: Variable Stars and the Stories They Tell by Mike Simonsen. * May 08: Peering Into the X-Ray Future by The Chandra X-Ray Center. * May 09: What's In a Day? by Cheap Astronomy. * May 10: The End of the Universe, In 10 Minutes by AstronomyCast. * May 11: The Magnetosphere by Terry and Stephan Whelan. * May 12: Dark Energy, with Michael Turner by Slacker Astronomy. * May 13: Messier's First Unique Find: Globular Cluster M3 by RapidEye Observatory.

The 7 days of 365 Days of Astronomy for week 18 2009. This week the shows include: * Apr 30: I'm Seeing Double! by Brains Matter. * May 01: Galileo, the Moon, and Visual Arts by James Clifton. * May 02: It's the Season for Eclipses in the Jupiter System by Jason Perry. * May 03: Webcam Astrophotography by Alexander W. Hobson. * May 04: Don't Forget Your Binoculars by Robin Scagell. * May 05: Seeing the Universe in a Whole New Light by Nicole Gugliucci. * May 06: All Aboard the Milky Way Railroad by Colin Stuart.

The 7 days of 365 Days of Astronomy for week 17 2009. This week the shows include: * Apr 23: It's a Smash-Up: Interacting Galaxies by Brian Gay. * Apr 24: My Astronomical Society by James O'Neill. * Apr 25: The Good, the Bad, and the Ugly of Outdoor Lighting by The U.S. National Park Service. * Apr 26: Palomar Observatory Honors Local Native Americans with Celestial Names by Scott Kardel. * Apr 27: Will the World End in 2012? by Cameron Hummels of Columbia Astronomy. * Apr 28: A Galaxy of Astronomical Birthdays by Patrick McQuillan. * Apr 29: The Big Picture by Carolyn Collins Petersen.

The 7 days of 365 Days of Astronomy for week 16 2009. This week the shows include: * Apr 16: What is the World's Largest Telescope? by Rob Sparks. * Apr 17: Giant Molecular Clouds by Sue Ann Heatherly. * Apr 18: Why Isn't Pluto a Planet? by AstronomyCast. * Apr 19: Ancient Indian Astronomy by Harith, Rahul, and Rohith. * Apr 20: Singing the Praises of the ISS by Nancy Atkinson. * Apr 21: The Six Enduring Mysteries of the Universe by Marc West. * Apr 22: Don't Forget Kepler by David Powell.

The 7 days of 365 Days of Astronomy for week 15 2009. This week the shows include: * Apr 09: SkyLab and the Apollo Telescope Mount by Josh Fuchs and Travis Rasor. * Apr 10: Build It and They Will Come: Tale of an Observatory by Ted Judah. * Apr 11: The ALMA Deep Field Experiment by Richard B. Drumm. * Apr 12: Exploring Space From Space by Kenneth Renshaw. * Apr 13: Edward, Annie, and Williamina Discuss Spectral Classification by Bruce Palmquist, Felicity Fredsti, and Marilyn Magenis. * Apr 14: Exploring Space with Your Computer by Bruce Irving. * Apr 15: Stargazing with Kids by Ed Sunder.

The 7 days of 365 Days of Astronomy for week 14 2009. This week the shows include: * Apr 02: Searching for Distant Hydrogen from the Australian Outback by Nicole Gugliucci. * Apr 03: Chicks In Space by Cheap Astronomy. * Apr 04: Census of the Solar System by Darren Bennett. * Apr 05: Astronomy in Canada: Past, Present, and Future by Alexander W. Hobson. * Apr 06: Chandra: Contemplating Infinity by Colin Stuart. * Apr 07: Can Visual Observers Still Contribute to Science? by The American Association of Variable Star Observers. * Apr 08: Drifting Through the Zodiac by Christopher Crockett.

The 7 days of 365 Days of Astronomy for week 13 2009. This week the shows include: * Mar 26: Adaptive Optics by Scott Kardel. * Mar 27: Observing the Sky: Pre-Telescope by The Adler Planetarium. * Mar 28: What If the Moon Did Not Exist? by Patrick McQuillan. * Mar 29: A Magnitude of Confusion by Chris Marr. * Mar 30: Robert Zubrin, on Why We Must Go to Mars by John C. Snider. * Mar 31: The Informative Dwarf Planet Haumea by Darin Ragizzone. * Apr 01: New Horizons: NASA's First Mission to Pluto by Andy Poniros

The 7 days of 365 Days of Astronomy for week 12 2009. This week the shows include: * Mar 19: Living with a Star: Space Weather and Its Effects by Carolyn Collins Petersen. * Mar 20: The Tradition of Looking Up by The National Park Service. * Mar 21: The March Equinox: All Latitudes are Illuminated by Judith Young. * Mar 22: Star Formation by Robert Simpson of Orbiting Frog. * Mar 23: Venus Moves From the Evening Sky to the Morning Sky by David Chapman. * Mar 24: Ptolemaic Cosmology - The Universe Before Copernicus by Nik Whitehead. * Mar 25: Selenography - Naming and Mapping the Moon by Mark Tillotson.

The 7 days of 365 Days of Astronomy for week 11 2009. This week the shows include: Mar 12: 365 Days of Astronomy Update by IYA New Media Working Group. Mar 13: Unlikely Twins in Gemini by Christopher Crockett. Mar 14: Globular Star Clusters: How Old Am I? Where Are You? by Richard Kinne. Mar 15: The Messier Objects by Ed Sunder. Mar 16: Using the Sun to Find the North Star by Ken Brandt. Mar 17: Echoes from a 430-year-old Supernova by Robert Knop. Mar 18: Milky Way Just Got Bigger by Sue Ann Heatherly.

The 7 days of 365 Days of Astronomy for week 10 2009. This week the shows include: Mar 05: Cool Comets by Martin Ratcliffe. Mar 06: GLOBE at Night: Shed Light on Light Pollution by Connie Walker. Mar 07: All About the AAVSO by The American Association of Variable Star Observers. Mar 08: Where Are Saturn's Rings? by Ted Haulley. Mar 09: Voyager: Sailing to the Edge of Our Solar System by Jane Platt. Mar 10: Talking to the Aliens by Steve Nerlich. Mar 11: History by Starlight by Colin Stuart.

The 7 days of 365 Days of Astronomy for week 09 2009. This week the shows include: Feb 26: Palomar Sky Surveys on Your Desktop by Scott Kardel Feb 27: The Dawning of the Age of Aquarius. Or is it? (Astrology Part 1) by Patrick McQuillan Feb 28: Edgar Allen Poe and the Riddle of Darkness at Night by Paul Halpern Mar 01: Exoplanet Roundup: Kepler's Planetary Peeking by Davin Flateau Mar 02: Astrosvenska For Anyone: Space Swedish in Ten Ridiculously Short Lessons by Robert Cumming Mar 03: Your Nook in the Incredible Universe by Dave Mosher Mar 04: Happy Birthday, Apollo! by Cheryl Hurkett and Alun Salt

The 7 days of 365 Days of Astronomy for week 08 2009. This week the shows include: Feb 19: Wil Tirion: Uranographer by Christopher Watson Feb 20: John Glenn's Fireflies and the Astronauts' Constellation by Robert Pearlman Feb 21: An Introduction to Chandra and the X-Ray Universe by The Chandra X-Ray Center Feb 22: Galileo's Plea to Return to Tuscany by Mark Thompson Feb 23: Astro-Engineering: Dyson Shells, Alderson Disks and Stellar Engines by Richard Stelling and Russell Mulligan Feb 24: Wolf-Rayet Stars by Ken Brandt Feb 25: One of Seven Stars of the Northern Dipper by Katja Algert

The 7 days of 365 Days of Astronomy for week 07 of 2009. This week the shows include: Feb 12: Eta Carinae and Supernova Imposters by Michael Koppelman Feb 13: A scale model of the Earth-Moon system by Bill Hudson Feb 14: Astronomical References in Shakespeare by Robert Knop Feb 15: The Life and Achievements of Galileo Galilei by Ted Haulley Feb 16: Steering by the Planets by Emily Lakdawalla Feb 17: Nicolaus Copernicus by John McFarland Feb 18: Pluto - The Planet that isn't a Planet Anymore by Susan Murph

The 7 days of 365 Days of Astronomy for week 06 of 2009. This week the shows include: 5 Feb: Motion through Space, by James A. Brown. 6 Feb: The 120th Anniversary of the Astronomical Society of the Pacific: The First National Astronomy Organization in the U.S., by Andrew Fraknoi. 7 Feb: Observing Variable Stars, by the American Association of Variable Star Observers (AAVSO). 8 Feb: The Paragould Meteorite of 1930, by Kenneth Renshaw. 9 Feb: Life and Death in Orion, by Christopher Crockett. 10 Feb: Humans are star stuff, by Carolyn Collins Petersen. 11 Feb: Exoplanet Remix by Davin Flateau.

The 7 episodes of 365 Days of Astronomy for week 05 of 2009.

The 7 episodes of 365 Days of Astronomy for week 04 of 2009.

The 7 episodes of 365 Days of Astronomy for week 03 of 2009.

The 7 episodes of 365 Days of Astronomy for week 02 of 2009.

The 7 episodes of 365 Days of Astronomy for week 01 of 2009.