Astronomy Cast Full Raw Feed

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.