Fraser Cain
Universe Today
Dr. Pamela Gay
CosmoQuest
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 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?
Recent Episodes
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 Venus-forming Earth. What are the various factors we're impacting on a global scale, and how can we fix them? We usually record...
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...
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!...
Human beings are bad at many things, but we're particularly terrible at understanding probability in a rational way. We underestimate, overestimate and generally mess up probability. We'll try to fix it here, but we'll surely fail. We usually record Astronomy Cast...
Small changes can have a big impact. But can a butterfly's wing-beat in the Amazon really impact the weather halfway across the world? And where do small changes have no impact? We usually record Astronomy Cast every Friday at 1:30 pm Pacific / 4:30 pm Eastern / 21:30...
Once again, science fiction television and movies has let you down. They try to recreate what it might be like on an alien world, but surprise surprise, they mostly get it wrong. That's because a truly alien world would be different in so many ways, it would blow your...
Mars is a world of extremes. This unassuming red world is home to the largest and tallest volcanoes in the entire Solar System. In fact, it's not even a close contest, with Olympus Mons rising 22 km above the surrounding plains, more than twice as tall as Mount...
Today, Mars is a desolate wasteland, with dusty red rocks and sand stretching out to the horizon. But billions of years ago, it was a vastly different world. It was blue, with oceans, rivers, lakes, and maybe life? Let's tell the story of geology on Mars, and we got...
We're fitting in one more episode this week, before Fraser heads off to Costa Rica for a week. Our next episode will record on Dec. 23, 2016. Enceladus and Europa are all the rage these days, but classic Mars is still a great place to search for life. In fact, ESA's...
Join us as we try to finish the interrupted episode Coming Home from Mars! Landing on the surface of Mars is very difficult. In fact, it's probably the toughest planet to land on in the whole Solar System. Today we'll talk about what it's going to take to get to and...
Hey folks, just letting you know that due to Fraser being at conference this week, we won't be recording an Astronomy Cast any time. Unfortunately, our last show was interrupted by a power outage, and we'll try to get back together to finish that one on Monday, 12/5....
Note - This episode was interrupted due to a power outage on Fraser's end. They'll reschedule to finish episode on 12/5 (most likely - Fraser is traveling this week!), and we'll put the pieces together when we have them and release as audio podcast! Landing on the...
When Elon Musk announced plans to send humans to Mars, he conveniently left out one important aspect. How are we supposed to survive on a place this hostile to life? Seriously, Mars sucks, and it's going to take some impressive techniques and technologies to make it...
We begin a miniseries on Mars. How many episodes will we do? Who knows? But we start today with a discussion of the two Mars moons, Phobos and Deimos. We usually record Astronomy Cast every Friday at 1:30 pm Pacific / 4:30 pm Eastern / 8:30 PM UTC (20:30 GMT). You can...
Did you hear that Dark Energy doesn't exist any more? Neither does Dark Matter? It turns out that NASA recalculated the Zodiac and now you're an Ophiuchan! Science is hard enough, but communicating that science out to the public when there are publications hungry for...
I hate to tell you this, but that meat computer in your skull is constantly betraying you. Don't worry, we've all got the same, but fortunately, scientists have learned how this happens, and can help us make sure our science, and lives don't suffer because of it. We...
Have you ever noticed spacecraft missions have some pretty cool names? How does anyone decide what to call these things? We usually record Astronomy Cast every Friday at 1:30 pm Pacific / 4:30 pm Eastern / 8:30 PM UTC (20:30 GMT). You can watch us live on...
It turns out that nature figured out how to use electricity long before humans did. Lightning storms are common across the Earth, and even the Solar System. What causes this electricity in the sky, and how can science use it? We usually record Astronomy Cast every...
As Hurricane Matthew reminded us, cyclonic storms are a force to be reckoned with. What causes these storms, and how can they form across the Solar System. We usually record Astronomy Cast every Friday at 1:30 pm Pacific / 4:30 pm Eastern / 8:30 PM UTC (20:30 GMT)....
So if you've been to Yellowstone National Park, you've seen one of the most amazing features of the natural world - geysers. In today's episode, we're going to talk about geysers on Earth, and where they might be in the solar system. We usually record Astronomy Cast...