Walkabout the Galaxy

An interstellar interloper may have been a chip off the old block, where the old block was a Pluto-like planet around another star, and the chip is solid air (nitrogen that is)! And we revisit the potential role of axions in the great dark matter chase and a new way that JWST may help us answer it. Join us for all that, exoplanets, science fiction trivia and more.

That's no error, this is episode 404, recorded in front of a live audience at DragonCon 2025 with special guest Trina Ray, Deputy Science Manager for the Europa Clipper mission. We get an update from the cool RADAR test the spacecraft conducted at Mars, new information on the history and composition of Interstellar Comet ATLAS 3/I and a super-duper-massive black hole. Join us for all this, 404 trivia, and more.

There is so much going on in the universe it's hard to keep track. That's why we have not one but two top astroquarks on this episode to cover the latest discoveries and news from the solar system to the deepest recesses of space. A search for a habitable atmosphere comes up empty, while a mission to study the loss of Mars' atmosphere nears launch. And a clever new technique may be able to detect the hypothesized axion, a candidate particle for dark matter. Check it out, with space news, trivia, and more.

There's more abundant and accessible water ice on Mars, ready for us to scoop it up, heat it up, and eat it up. And in the distant recesses of the universe there's a supermassive black hole with an interesting neighbor that causes a periodic splash of light. Learn all about it, plus trivia, fake sponsor, the Earth's puzzling spin, and much more.

We discuss the largest black hole merger observed to date, between two black holes that are in the so-called forbidden mass range. They must have been created by some ancient merger of other black holes themselves. It's black holes everywhere you look these days. Closer to home, we take a look at Europa's weird Chaos terrain and new insights on how Mars lost its atmosphere. We also get a shout out from Audrey's dog.

The astroquarks celebrate 400 episodes with a special sponsor, a special stumper, and a special interstellar comet making its way through our solar system from an origin near the galactic center perhaps as much as 7 billion years ago.

The Vera C. Rubin Observatory has started making observations with the world's largest optical detector boasting over 3 billion pixels at the back of an enormous telescope in the high Andes. We take a look at some of the early discoveries and look ahead to what's in store for this enormous project as it plans to scan the sky hundreds of times at unprecedented detail over the course of the next decade. Plus: astronomy trivia, science hot takes, and more.

We're all about the weather on this episode, with a new study showing that even relatively distant supernova may have affected the Earth's climate in the recent past. And the James Webb Space Telescope has observed exoplanet WASP-107b to have clouds of sand vapor. Plus, we have two hot takes and two Top astroquarks!

Original top quark Tracy Becker is back to bring us up to speed Europa Clipper's flyby of Mars, and we learn about a new way for planetary cores to form without so much heat. Join us for all this, plus lava fountain trivia, space news, and much more.

A major update to the predicted end of the universe has it coming much earlier than previously anticipated. However, we still have plenty of time to get our affairs in order, and the update has to do with spaghettification, and anything with spaghettification can't be all bad. We also talk about active asteroids, your ideal night sky, and cosmological trivia.