Walkabout the Galaxy

An irreverent and informative tour of the latest, greatest, and most interesting discoveries in astronomy.

Supernovas and Mass Extinctions 04/02/2025

Supernovas and Mass Extinctions A survey of nearby stars establishes the rate of supernovas in our general neighborhood. Evidence indicates we had nearby stellar explosions at the times of two mass extinctions. Those supernovas may have decimated the ozone layer and contributed to extinctions and climate changes. Plus, we recorded on April 1 and take a look at silly April 1 science papers, and we get tilted with our trivia and space news. Join us, won't you? /episode/index/show/walkaboutthegalaxy/id/35975860

Life on Hycean Worlds, Interstellar Debris, and Dark Matter Survey 03/26/2025

Life on Hycean Worlds, Interstellar Debris, and Dark Matter Survey If there are Hycean worlds and if they have a certain kind of microbial life and if there is enough of it, JWST might be able to see the chemical products of that in the planet's atmosphere. We take a look at that, debris from neighboring stars entering our solar system, and the first results from the Euclid space telescope. Join us for all this plus a hilarious double stumper and more. /episode/index/show/walkaboutthegalaxy/id/35870575

Are We Inside a Black Hole? 03/19/2025

Are We Inside a Black Hole? There are exciting new observations from recent lunar missions, a possible chunk of the Moon keeping us company, and an intriguing observation supporting the theory that the entire universe is inside a black hole! Get inside the event horizon with the astroquarks for all the space updates, trivia, and more. /episode/index/show/walkaboutthegalaxy/id/35768895

Oort Cloud Spiral, the Color of Mars, and a New Dwarf Galaxy 03/05/2025

Oort Cloud Spiral, the Color of Mars, and a New Dwarf Galaxy We take a look at the formation and structure of the Oort cloud of comets which is spherical at large distances but has a spiral structure in its inner regions. And, after all this time, there's a surprising twist on the nature of the iron mineral that gives Mars its reddish hue. Also hiding in plain sight is a dwarf galaxy in the neighborhood of the Andromeda galaxy, our largest companion galaxy. Join us for a discussion of these discoveries, trivia, space news and more. /episode/index/show/walkaboutthegalaxy/id/35528390

Did You Quipu? 02/26/2025

Did You Quipu? Lunar exploration continues to accelerate, and there's a new longest "structure" in the universe. Quipu is a quasi-alignment of clusters of galaxies stretching over 1 billion light years. Structure is in cynical quotation marks because these objects are not bound or connected to each other in any way, but their arrangement is a natural consequence of the evolution of the universe. If we happen to be in a Quipu-like structure ourselves, that may help us get out of our Hubble tension problem. Join us for cosmological mind-benders like this, and updates on ocean worlds and other moons closer to home, as well as space news and trivia. /episode/index/show/walkaboutthegalaxy/id/35431710

Hubble Tension Won't Go Away But Some Exoplanets Do 02/12/2025

Hubble Tension Won't Go Away But Some Exoplanets Do The more measurements we make of the expansion of the universe, the more it seems as though Hubble Tension is not a problem with our data but a problem with our understanding of the expansion of the universe. We'll talk about that, and some cool new observations closer to home, including a disintegrating exoplanet that is giving us a unique peak into a planet's insides. Join us for all this and more, including space news and trivia. /episode/index/show/walkaboutthegalaxy/id/35245345

Exocomets, Io, and the Great Dimming of T Tauri 01/29/2025

Exocomets, Io, and the Great Dimming of T Tauri Juno reveals a surprise about the interior of Jupiter's volcanic moon Io, and the OG young variable star T Tauri is getting ready to fade from view thanks to its dusty neighbors to the south. Speaking of dust, that's what gets kicked up when comets collide, and a new survey examines the cometary belts around dozens of star systems, providing a detailed look at the outer reaches of exoplanetary systems. Join us for all this, sample return stumpers, and Top Quark trivia. /episode/index/show/walkaboutthegalaxy/id/35017685

Little Red Dots and Big Black Holes 01/22/2025

Little Red Dots and Big Black Holes The discoveries from the James Webb Space Telescope keep coming. After showing that galaxies formed far earlier than we thought, we now have a better understanding of what was going on in the early universe. Those little red dots spied by JWST are actually the glow of heated dust and gas from supermassive black holes, and not the glow from billions of stars as had been thought. Closer to home, did the Earth sport a ring for a few million years? Analysis of ancient craters suggests it may have. Tune in to get the full story, plus gravitational trivia, space news, and more. /episode/index/show/walkaboutthegalaxy/id/34943090

Kiss and Capture for Pluto and Charon and Dark Energy Remains Dark 01/15/2025

Kiss and Capture for Pluto and Charon and Dark Energy Remains Dark Pluto and its largest moon, Charon, orbit each other with gazes lovingly fixed on each other, held in place by a romantic tidal attraction. But Charon's large size has always been difficult to explain. New simulations show that their love affair may have started at the beginning with a "Kiss and Capture" collision, much gentler than the devasting impact that formed our own Moon. Hear all about that, Centaurs, space news, space trivia, and a new way to explain away Dark Energy with your friendly neighborhood astroquarks. /episode/index/show/walkaboutthegalaxy/id/34826625

Quasi Particles, Pluto's Moons, and Cosmic Rays 01/08/2025

Quasi Particles, Pluto's Moons, and Cosmic Rays We kick off 2025 with oddities from quasi particles, to cosmic rays, to the moons of Pluto. What has mass when it moves in one direction and doesn't when it moves in another direction? How do thunderstorms on Earth interact with cosmic rays? What is up with Pluto's moons? Join us as we tackle these questions as well as the stumper and special top quark trivia. It's all part of the package in an episode of Walkabout the Galaxy. /episode/index/show/walkaboutthegalaxy/id/34768130

Mysterious Dark Comets 12/18/2024

Mysterious Dark Comets We know about extinct comets and active asteroids, but now we've got something in between: dark comets, whose orbits indicate cometary activity, but we can't see it! We'll get the scoop on these interesting objects, a flare from a supermassive black hole, and a twist on the question of the age of Saturn's rings. Plus, we have our end-of-the-year rocket launch roundup, and a special astrophysical FLOD stumper for top quark Jim Cooney. /episode/index/show/walkaboutthegalaxy/id/34495540

Making Big Blobs is Hard 12/11/2024

Making Big Blobs is Hard Top quark Jim Cooney explains why making big blobs is hard and how new observations are helping us understand how the universe made big immensely big blobs more commonly known as giant elliptical galaxies. Nature loves to make a disk, and we love to tell you all about the cool things nature does, including a solid state greenhouse on ancient Mars that may have produced a huge buried supply of water to create giant rivers near its south pole. Join us for this and more mind-blowing stuff. It's all part of our Walkabout the Galaxy. /episode/index/show/walkaboutthegalaxy/id/34358820

Neutrino Fog and the Hunt for Dark Matter 11/27/2024

Neutrino Fog and the Hunt for Dark Matter It's a good news bad news story with the detection of the neutrino fog. This signal from solar neutrinos may confound our search for certain dark matter candidates, but at least we know our detectors are very, very sensitive! We also take a look at magnetic fields in the outer solar system, specifically why Uranus's magnetosphere was so weird when we visited in 1986, and what tiny grains from a near Earth asteroid may be telling us about the magnetic field four and a half billion years ago. Join us for all that, and of course space news and stupid trivia. /episode/index/show/walkaboutthegalaxy/id/34150880

Not All Supernovae Are Created Equal 11/20/2024

Not All Supernovae Are Created Equal If you're speaking English, not Latin, do you really have to say "supernovae" instead of "supernovas"? Also, they are, in some sense, created equally: explosion of a white dwarf, but the outcomes are not all equal. You are welcome for this grammatical tangent, and please enjoy our fun discussion about weird tesserae (more Latin!) on Venus and the whole standard candle story of type 1a supernovae gets a rewrite. On this episode of Walkabout the Galaxy, you can also enjoy solar energy/spacecraft trivia, space news, and general hilarity at no extra charge. /episode/index/show/walkaboutthegalaxy/id/34018752

Is There Another Belt of Comets? 11/06/2024

Is There Another Belt of Comets? New observations contradict earlier studies about the possibility of another belt of comets orbiting the Sun twice as far away as Pluto. We'll take a look at what's what in the outer solar system and also explore whether black holes may help explain the Hubble tension. We also play FLOD (Flyby, Land, Orbit, Destroy) and have some "how many planets" trivia. /episode/index/show/walkaboutthegalaxy/id/33757257

Trojan Asteroids Everywhere 10/30/2024

Trojan Asteroids Everywhere Join Strange and Down quarks for a close look at Trojan asteroids, the forgotten asteroids of the solar system. NASA's Lucy mission is en route to take our first close look at these denizens of the outer solar system and has an Earth gravity assist in December 2024. As you'll see in our trivia, the numbers of Trojans may surprise you. Jupiter is the king of the Trojans, but we'll take a closer look at the first comfirmed Trojan of Saturn. /episode/index/show/walkaboutthegalaxy/id/33679492

Basin Instinct - Cosmological Structure and Edible Asteroids 10/23/2024

Basin Instinct - Cosmological Structure and Edible Asteroids We get a tour of our place in the grand cosmological scheme of things with new mapping of the local Basin of Attraction. Spoiler: also Jim's new stage name. And we explore the final frontier of In Situ Resource Utilization with studies of how to get edible nutrients from the raw materials in asteroids. It's a little bit gross. Plus space news, trivia, and more. Join us to learn about all this (and all of our new stage names). /episode/index/show/walkaboutthegalaxy/id/33567067

OG Top Goes to Europa 10/09/2024

OG Top Goes to Europa Original Top Quark Dr. Tracy Becker returns to her old stomping grounds to hang with the Walkabout crew and send Europa Clipper on its way to Jupiter. Join us for a preview of this mission's ambitious goals and the exciting journey it took to the launch pad. Also, new research suggests the Earth may escape a fiery death when the Sun becomes a red giant. We have, of course, space news, space history trivia, and much more. /episode/index/show/walkaboutthegalaxy/id/33369782

Back in Black Holes 10/02/2024

Back in Black Holes We’ve got mini black holes as potential dark matter candidates and monstrous black holes spewing jets to cosmological scales. Who better than Top quark Jim Cooney to take us through these black holes? No one, that’s who. We take a deep dive into meteorites, particularly those that have come from Mars. You may be surprised to learn how many we have, and now we know more about where those free Mars samples originated from on the red planet. Join us for all this, space news, and trivia. /episode/index/show/walkaboutthegalaxy/id/33291762

Black Hole Spindown Chirp and a 9-Day Geologic Rumble 09/18/2024

Black Hole Spindown Chirp and a 9-Day Geologic Rumble Gravitational waves may provide a new way to observe supernovae in our own Milky Way galaxy and determine when they produce black holes and when they result merely in neutron stars. Closer to home, scientists did some clever detective work to figure out the source of a mysterious 9-day seismic shaking here on Earth. The culprit: a giant, regular sloshing in a fjord triggered by a landslide as a result of warming temperatures and melting land ice. Join us for this and other astro news including an interesting mini-moon and funny science lingo. /episode/index/show/walkaboutthegalaxy/id/33056297

Recent Lunar Volcanic Activity and the Metallicity Cliff 09/11/2024

Recent Lunar Volcanic Activity and the Metallicity Cliff Tiny samples brought back from the Moon hint at surprisingly recent volcanic activity. What's up with that?! Elsewhere in the galaxy, a detailed study of over 100,000 stars identifies the metallicity cliff. This is where stellar composition that is low in heavy elements seems to inhibit the formation of at least some types of exoplanets. The astroquarks have all the details for you, as well as a Polaris Dawn update and nerd trivia. Join us, won't you? /episode/index/show/walkaboutthegalaxy/id/33002137

Adventures in Space the Cady Way 09/04/2024

Adventures in Space the Cady Way The Astroquarks are joined by former NASA astronaut, PhD Chemist, and retired USAF Colonel Cady Coleman at Dragon Con 2024 for a wide ranging discussion of space flight, institutional challenges, training, flute playing, and more. /episode/index/show/walkaboutthegalaxy/id/32900587

Ocean World Mimas and the JUICE Slingshot 08/28/2024

Ocean World Mimas and the JUICE Slingshot Recent (astronomically speaking, of course!) perturbations to Mimas's orbit may be the explanation for the surprising presence of a global subsurface ocean in this tiny moon of Saturn. Meanwhile, the European Space Agency's JUICE (Jupiter Icy Moon Explorer) mission successfully completed a novel gravity assist making use of the Earth's Moon and the Earth to send it towards... Venus! We have all the explanations, space travel stumpers, trivia and more. /episode/index/show/walkaboutthegalaxy/id/32734362

Barney the Dinosaur Killer from Outer Space and Water Inside Mars 08/21/2024

Barney the Dinosaur Killer from Outer Space and Water Inside Mars New research shows that the asteroid that killed the dinosaurs some 66 million years ago formed in the colder, more distant reaches of the solar system. The Astroquarks have taken it upon themselves to dub this asteroid Barney. We’ll update you on that new research and a surprising discovery from Mars Insight data that suggests Mars has a potentially huge amount of delicious H2O not to far beneath its surface. It’s just a bit dirty, is all. And we have lots of space news, stumpers, and more. Join us, won’t you? /episode/index/show/walkaboutthegalaxy/id/32629057

The Fermi Paradox - Are We Truly Alone? 08/14/2024

The Fermi Paradox - Are We Truly Alone? When Frank Drake created his famous eponymous equation to estimate the number of advanced communicative civilizations in the Milky Way, we had little more than educated guesses for most of the factors in that equation. Decades later we have much better data, and the answer seems to reinforce Fermi's famous paradox: why is our galaxy so silent? The role of plate tectonics in enabling evolution of advanced life forms is examined in new research were a revision to the Drake Equation is proposed, and the unsettling answer may be that we are truly alone. /episode/index/show/walkaboutthegalaxy/id/32545377

Chemical Whispers of Life on Mars 07/31/2024

Chemical Whispers of Life on Mars The astroquarks assemble for their 365th episode, about 10 years after their first, with a look at a canceled mission to the Moon and tantalizing observations from an ongoing mission at Mars. The Perseverance rover has spied a particularly unusual rock sample with some tantalizing features. Join us for the deets as well as historical astronomy trivia, space news, and more. /episode/index/show/walkaboutthegalaxy/id/32375432

Lunar Caves for Future Habitation 07/18/2024

Lunar Caves for Future Habitation In this light episode of Walkabout the Galaxy, Josh and Audrey discuss the first confirmation of open spaces in lava tubes connected to lunar pits on the Moon. 200 lunar pits have been observed on the Moon, and now scientists have used radar data to demonstrate that these pits are in fact connected to caverns that could provide future astronauts with a safe haven beneath the lunar surface. Join us on this short walkabout for the full story, trivia, and space news updates. /episode/index/show/walkaboutthegalaxy/id/32202222

Dark Matter, Deuterons, and a Mixed-Up Protoplanetary Disk 07/11/2024

Dark Matter, Deuterons, and a Mixed-Up Protoplanetary Disk You'll be amazed at how much we can learn from iron meteorites. Who would have guessed that analysis of the compositions of these humble metallic remnants of asteroids would be able to tell us about the shape of the protoplanetary disk? We'll learn about the latest clues to the early history of our solar system, the surprising abundance of deuterons in cosmic rays provides another indicator that we still have a lot to learn about the early universe, and dark matter - well it's still out there, still dark. Join us for all this, space news, nerdy trivia and more. /episode/index/show/walkaboutthegalaxy/id/32102612

Cygnus X-3 and a Naked-Eye Nova 06/27/2024

Cygnus X-3 and a Naked-Eye Nova The clock is ticking on T Coronae Borealis which seems primed to undergo a nova explosion this summer. That will make this otherwise faint star as bright as Polaris thanks to a burst of nuclear fusion reactions on the exposed surface of this white dwarf. Another curious binary system, Cygnus X-3, is beaming x-rays toward us thanks to some nifty photon processing in the disk surrounding this black hole. Learn more about these cool systems, parallel universes, dense moons and more with your friendly neighborhood astroquarks. /episode/index/show/walkaboutthegalaxy/id/31913247

Primordial Black Holes Make the Galaxy Go 'Round 06/20/2024

Primordial Black Holes Make the Galaxy Go 'Round We take a look at some Beta Pic Disk shots before journeying back to the earliest era of the universe and the possible formation of primordial black holes. Some of these may have been only the size of an atom and would have long since evaporated through Hawking radiation. But they may have left an observable imprint for our powerful telescopes peering into the distant past, and their larger siblings are a possible contender for dark matter. Join us for all this, space news, silly trivia, and much more. /episode/index/show/walkaboutthegalaxy/id/31822682

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