Walkabout the Galaxy
Episodes
A Whisper of a Hint of Primordial Black Holes plus Earth BLOBs
18 Mar 2026
Contributed by Lukas
Gravitational Wave observatory LIGO has seen a signature that looks like the merger of primordial (pre-stellar, big bang (not big band!) era) black ho...
Supermassive Black Holes Supersoaking Other Galaxies
25 Feb 2026
Contributed by Lukas
Supermassive black holes can be terrible neighbors. New research shows that their powerful jets of charged particles can shut down star formation in n...
Snowball Earth was Cold and Scary and the Milky Way Magnetic Field is a Mess
18 Feb 2026
Contributed by Lukas
The Earth spent some crazy amounts of time (tens of millions of years) completely frozen over. And not, in the grand scheme of things, all that long a...
Planetary Nebulae and Active Asteroids Get a Closer Look
05 Feb 2026
Contributed by Lukas
There's always been a fuzzy line between asteroids and comets, and new observations of asteroids in the vicinity of Jupiter provide a hint to the orig...
A Dark Universe Unveiled
29 Jan 2026
Contributed by Lukas
Scientists head to the volcanic fields of Iceland to test instruments for the VERITAS mission to Venus, Artemis II is ready for its historic flight to...
Crazy Spinners in the Asteroid Belt and S8 Tension
14 Jan 2026
Contributed by Lukas
The amazing discoveries from the Vera C. Rubin Observatory have already started, and the astroquarks take a look at some close to home. Asteroids bigg...
Cosmic Rays from Everywhere and Stringy Ancient Galaxies
17 Dec 2025
Contributed by Lukas
The Parker Solar Probe flies through the Sun's corona, MAVEN has gone silent, and new data shed light on the origins of cosmic rays. JWST's observatio...
Interstellar Star Scars and Poop on Mars
10 Dec 2025
Contributed by Lukas
We explore the dining and drinking choices for astronauts, complex chemicals discovered in asteroid samples, and untangling the web of scars in the lo...
Gravothermalizing and Baby Black Holes
04 Dec 2025
Contributed by Lukas
There's a new funky proposal for small black holes in the early universe, and another potential dark matter candidate. Learn about cannibal stars and ...
An Ancient Moon of Mars?
26 Nov 2025
Contributed by Lukas
The story behind this investigation is almost more cool than the discovery itself. Microlayers of sediments in Mars' Gale Crater, observed by NASA's C...
Why Is There A Universe At All?
20 Nov 2025
Contributed by Lukas
Things would be a lot simpler and a lot less interesting if charge parity existed in the universe, but there would be no one to appreciate that simpli...
The Amazing and Crazy Story of Gemini and Jumbo Black Holes
05 Nov 2025
Contributed by Lukas
The astroquarks are joined by Jeffrey Kluger, editor at large at Time Magazine and author of 13 books including Apollo 13 and the new book on the Gemi...
Rings Around a Comet, Betelbuddy, and Odd Jupiter Moons
29 Oct 2025
Contributed by Lukas
These rings aren't around Uranus, they're somewhere even more odd. We discuss the mysterious and changing ring system around the Centaur object Chiron...
Adaptive LIGO and a New Look at an Old Crater
01 Oct 2025
Contributed by Lukas
Adaptive optics techniques get applied to the mirrors in the LIGO gravitational wave observatory, promising a five-fold or greater improvement in sens...
Einstein Cross Reveals Dark Matter and a Life-y Mars Rock
24 Sep 2025
Contributed by Lukas
We take a look the Cheyava Falls rock on Mars, or rather the Perseverance rover took a look at it, and we discuss what it saw which were some intrigui...
Exo-Pluto Debris in Our Solar System and Axions Galore
10 Sep 2025
Contributed by Lukas
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 so...
Europa Clipper Report from Mars and ATLAS 3I Update from DragonCon 2025
03 Sep 2025
Contributed by Lukas
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 ...
Trappist-1, ESCAPADE, and Axions
20 Aug 2025
Contributed by Lukas
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 lat...
Weird Black Hole Blazar and Water Ice Glaciers on Mars
06 Aug 2025
Contributed by Lukas
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 uni...
Forbidden Black Hole Merger and Chaos on Europa
30 Jul 2025
Contributed by Lukas
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...
Interstellar Comet 3I/ATLAS is Out Of This World
16 Jul 2025
Contributed by Lukas
The astroquarks celebrate 400 episodes with a special sponsor, a special stumper, and a special interstellar comet making its way through our solar sy...
Vera Rubin Observatory Sets Sights on the Universe
02 Jul 2025
Contributed by Lukas
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 ...
Supernova Hazards and Cloudy With a Chance of Sand
18 Jun 2025
Contributed by Lukas
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 ...
Cool Planetary Cores and Lava Fountains Galore
04 Jun 2025
Contributed by Lukas
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 fo...
The End of the Universe As We Know It and We Feel Fine
21 May 2025
Contributed by Lukas
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 g...
A Slurping Black Hole and a Win for the Streaming Instability
14 May 2025
Contributed by Lukas
We get lucky and catch a rogue supermassive black hole in the act of slurping up a star as it meanders through a distant galaxy. Closer to home, the d...
Vesta Chip Off the Old Block and a Nearby Dark Molecular Cloud
07 May 2025
Contributed by Lukas
The asteroid Vesta may be a fragment of a much larger protoplanet, and astronomers examine old data to discover a large molecular cloud lurking right ...
Ultralight Dark Matter and Peanut Asteroid Hot Take
30 Apr 2025
Contributed by Lukas
NASA's Lucy mission had a picture perfect encounter with the asteroid Donaldjohanson on its way to the first ever flybys of Trojan asteroids. Discover...
Hot Takes on Water on Earth and Black Hole Singularities
23 Apr 2025
Contributed by Lukas
The astroquarks discover hot takes and explore the nature of ice, the origin of Earth's water, and the trouble with the singularities at the hearts of...
Weird Convection on Venus and a Wrinkle in the Lambda Cold Dark Matter Model
09 Apr 2025
Contributed by Lukas
Venus's extra-thick crust may be extra chewy, allowing convection to occur and helping power volcanoes into the current era. New observations of the d...
Supernovas and Mass Extinctions
02 Apr 2025
Contributed by Lukas
A survey of nearby stars establishes the rate of supernovas in our general neighborhood. Evidence indicates we had nearby stellar explosions at the ti...
Life on Hycean Worlds, Interstellar Debris, and Dark Matter Survey
26 Mar 2025
Contributed by Lukas
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 prod...
Are We Inside a Black Hole?
19 Mar 2025
Contributed by Lukas
There are exciting new observations from recent lunar missions, a possible chunk of the Moon keeping us company, and an intriguing observation support...
Oort Cloud Spiral, the Color of Mars, and a New Dwarf Galaxy
05 Mar 2025
Contributed by Lukas
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 inne...
Did You Quipu?
26 Feb 2025
Contributed by Lukas
Lunar exploration continues to accelerate, and there's a new longest "structure" in the universe. Quipu is a quasi-alignment of clusters of galaxies s...
Hubble Tension Won't Go Away But Some Exoplanets Do
12 Feb 2025
Contributed by Lukas
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 proble...
Exocomets, Io, and the Great Dimming of T Tauri
29 Jan 2025
Contributed by Lukas
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 th...
Little Red Dots and Big Black Holes
22 Jan 2025
Contributed by Lukas
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 ...
Kiss and Capture for Pluto and Charon and Dark Energy Remains Dark
15 Jan 2025
Contributed by Lukas
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...
Quasi Particles, Pluto's Moons, and Cosmic Rays
08 Jan 2025
Contributed by Lukas
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 w...
Mysterious Dark Comets
18 Dec 2024
Contributed by Lukas
We know about extinct comets and active asteroids, but now we've got something in between: dark comets, whose orbits indicate cometary activity, but w...
Making Big Blobs is Hard
11 Dec 2024
Contributed by Lukas
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 ...
Neutrino Fog and the Hunt for Dark Matter
27 Nov 2024
Contributed by Lukas
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 matt...
Not All Supernovae Are Created Equal
20 Nov 2024
Contributed by Lukas
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:...
Is There Another Belt of Comets?
06 Nov 2024
Contributed by Lukas
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 ...
Trojan Asteroids Everywhere
30 Oct 2024
Contributed by Lukas
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 tak...
Basin Instinct - Cosmological Structure and Edible Asteroids
23 Oct 2024
Contributed by Lukas
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...
OG Top Goes to Europa
09 Oct 2024
Contributed by Lukas
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....
Back in Black Holes
02 Oct 2024
Contributed by Lukas
We've got mini black holes as potential dark matter candidates and monstrous black holes spewing jets to cosmological scales. Who better than Top quar...
Black Hole Spindown Chirp and a 9-Day Geologic Rumble
18 Sep 2024
Contributed by Lukas
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 ...
Recent Lunar Volcanic Activity and the Metallicity Cliff
11 Sep 2024
Contributed by Lukas
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...
Adventures in Space the Cady Way
04 Sep 2024
Contributed by Lukas
The Astroquarks are joined by former NASA astronaut, PhD Chemist, and retired USAF Colonel Cady Coleman at Dragon Con 2024 for a wide ranging discussi...
Ocean World Mimas and the JUICE Slingshot
28 Aug 2024
Contributed by Lukas
Recent (astronomically speaking, of course!) perturbations to Mimas's orbit may be the explanation for the surprising presence of a global subsurface ...
Barney the Dinosaur Killer from Outer Space and Water Inside Mars
21 Aug 2024
Contributed by Lukas
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 syste...
The Fermi Paradox - Are We Truly Alone?
14 Aug 2024
Contributed by Lukas
When Frank Drake created his famous eponymous equation to estimate the number of advanced communicative civilizations in the Milky Way, we had little ...
Chemical Whispers of Life on Mars
31 Jul 2024
Contributed by Lukas
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 obse...
Lunar Caves for Future Habitation
18 Jul 2024
Contributed by Lukas
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 ...
Dark Matter, Deuterons, and a Mixed-Up Protoplanetary Disk
11 Jul 2024
Contributed by Lukas
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 remn...
Cygnus X-3 and a Naked-Eye Nova
27 Jun 2024
Contributed by Lukas
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 bri...
Primordial Black Holes Make the Galaxy Go 'Round
20 Jun 2024
Contributed by Lukas
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 h...
Full Circle to the Origins of Carbon and Exotic Gravity
12 Jun 2024
Contributed by Lukas
The Astroquarks celebrate their 360th episode with discoveries showing carbon much earlier in the universe than previously thought possible, and an ex...
Volcanic Activity on Venus RIGHT NOW!
05 Jun 2024
Contributed by Lukas
There is a mountain - or should we say a volcano - of evidence, building that suggests volcanic activity on Venus during the time of the Magellan miss...
Watery Erigone and Rogue Stars in the Milky Way
30 May 2024
Contributed by Lukas
New observations of Erigone, the parent body of an asteroid family, indicate its rocks are juicy with water. That makes it both a potential resource f...
Dyson Spheres and a Molten Planet
15 May 2024
Contributed by Lukas
The Astroquarks delve into the possibility of giant alien constructs around stars, and the strange weather on a planet that is unreasonably close to i...
The Low Down on Big G and the Young Moon of Dinkinesh
08 May 2024
Contributed by Lukas
NASA's Lucy mission discovered a surprising moon of the small asteroid Dinkinesh on its way to the orbit of Jupiter. New studies of that moon, a conta...
Dark Matter Wins Again
01 May 2024
Contributed by Lukas
A clever test of dark matter and an alternative theory of gravity to explain the motions of stars around galaxies results in another check in the win ...
Surprises from Bennu and the Milky Way
03 Apr 2024
Contributed by Lukas
Analysis of the samples returned from the asteroid Bennu have revealed surprising assemblages of minerals that put new constraints on the origin of th...
The Dark Ages of the Universe
27 Mar 2024
Contributed by Lukas
We peer back in time both to the murky history of our own solar system and to the dark ages of the universe. The JWST has confirmed that dwarf galaxie...
A Nova Visible this Year?
20 Mar 2024
Contributed by Lukas
One of only a handful of recurrent novas, white dwarf stars that undergo a periodic explosive brightening as they accrete material from a neighboring ...
Psyche Revisited and Two Giant Black Holes
06 Mar 2024
Contributed by Lukas
The presumed metallic asteroid Psyche gets a new look before the spacecraft of the same name gets there in 2029, and it reveals different spectral cha...
The Tiniest Ocean World and the Brightest Quasar
28 Feb 2024
Contributed by Lukas
Saturn's so-called Death Star moon Mimas may harbor a global subsurface ocean based on analysis of Cassini data of the tiny moon's orbit and rotation....
Space Oddities in the Solar System
21 Feb 2024
Contributed by Lukas
Water molecules have been observed on the surface of an asteroid for the first time, and new studies help explain some of the odd behavior of planetar...
When Will We Walk on Mars?
07 Feb 2024
Contributed by Lukas
In this special episode recorded live at MegaCon Orlando 2024, we are joined by NPR space reporter Brendan Byrne to take a close look at where we are ...
Large Cosmological Structures and JWST Spies a Binary TNO
31 Jan 2024
Contributed by Lukas
There's another claim for a violation of the cosmological principle - that all parts of the universe are basically the same on large scales - but Top ...
Trojan Mysteries and Titan Snowbergs
24 Jan 2024
Contributed by Lukas
Strange disappearing islands in the hydrocarbon lakes of Saturn's giant moon Titan may be fluffy icebergs of hydrocarbon snow. If you're on Titan, def...
Agents of Chaos and Iron Snow
10 Jan 2024
Contributed by Lukas
What role has Jupiter played in the existence of our warm and cosy home planet? Has it been bravely using its gravity to keep the inner solar system c...
Globular Clusters and Life in Enceladus
21 Dec 2023
Contributed by Lukas
New analysis of Cassini data suggests more complex hydrocarbons are part of Enceladus's global sub-surface ocean. We discuss the prospects for life on...
Pluto Cryovolcano and a Cosmological Supervoid
13 Dec 2023
Contributed by Lukas
At Pluto's frigid temperatures, even what we breathe is frozen. This can give rise to unusual cryovolcanism, and new research suggests a super cryovol...
Mysterious Cosmic Ray and Martian Airglow
06 Dec 2023
Contributed by Lukas
The second most energetic cosmic ray (really a particle) ever observed smashed into the Earth a couple of years ago, raising more questions about the ...
Ethical Dilemmas in Space Exploration
22 Nov 2023
Contributed by Lukas
The astroquarks are joined by Dr. Erika Nesvold, astrophysicist and author of "Off Earth: Ethical Questions and Quandaries for Living in Outer Space" ...
The Origin of Supermassive Black Holes
15 Nov 2023
Contributed by Lukas
JWST data confirm early formation of supermassive black holes, less than 500 million years after the big bang. This early formation suggests these mon...
Dinky and the S8 Tension
08 Nov 2023
Contributed by Lukas
The Lucy spacecraft had its first asteroid encounter, revealing Dinkinesh to be a binary asteroid. In cosmology, a new simulation with a terrible ac...
The Surprising Interiors of Mars and Venus
01 Nov 2023
Contributed by Lukas
New research suggests that Venus, Earth's twin gone bad, may have started off with tectonic plate activity, like Earth. This will help us understand t...
Detecting ETs and Intergalactic Baryons
25 Oct 2023
Contributed by Lukas
Fast Radio Bursts are back, this time providing a crucial measurement of the amount of normal matter in the universe. Top quark Jim Cooney explains ho...
Neutron Star Quakes and the Streaming Instability
18 Oct 2023
Contributed by Lukas
Images of the distant Kuiper Belt Object Arrokoth add more weight to the pebble accretion model of planetesimal formation via the streaming instabilit...
Pangaea Ultima, Antimatter Gravity, and the Evection Resonance
04 Oct 2023
Contributed by Lukas
The next supercontinent could spell bad news for mammals. The equivalence principle passes another test, with antimatter atoms falling just like norma...
Short Take: Asteroid Sample and Dark Matter Hopes
27 Sep 2023
Contributed by Lukas
Strange and Top discuss the return of the sample from the asteroid Bennu and an intriguing measurement from a dark matter detector in Italy in this, o...
Trouble in the Universe: El Gordo and Dinky
20 Sep 2023
Contributed by Lukas
There's more tension in the standard model of the history of the universe. Giant superclusters of galaxies formed early than we thought they could. Th...
Ho'oleilana and Weird Spots on Mercury
13 Sep 2023
Contributed by Lukas
This episode is about hollows in space on very different scales and for very different reasons. Ho'oleilana is the largest observed structure in the u...
Water in the Solar System - Dragoncon 2023
07 Sep 2023
Contributed by Lukas
The astroquarks report from Dragoncon 2023 on the surprisingly diverse distribution of water in the solar system, where it came from, and the prospect...
Diamonds, Granite, and Hubble Tension
30 Aug 2023
Contributed by Lukas
When we think of all the wonderfully unique things about the Earth as a planet (liquid water on the surface, life, plate tectonics), the existence of ...
The Sun Bounces Gamma Rays and a Muon Surprise
16 Aug 2023
Contributed by Lukas
The Sun is showering us with far more gamma rays than anticipated according to new measurements from a Cerenkov radiation detector in Mexico. The way ...
Rogue Planets Galore and the Age of the Universe
09 Aug 2023
Contributed by Lukas
We take a look at two extraordinary astronomical news items in this episode. A deep dive into an astronomical survey has discovered an Earth-sized rog...
Dark Stars and Water in Hot Places
02 Aug 2023
Contributed by Lukas
The JWST has spotted water vapor in the hot inner region of a protoplanetary disk, the same region where rocky planets like are own are expected to fo...
X-Rays from Mercury and a Different Kind of Gravitational Hole
26 Jul 2023
Contributed by Lukas
We think of aurora as an atmospheric phenomenon, but what happens when high energy particles from the Sun directly impact a planetary surface? Mercury...
The Rumble in the Universe
12 Jul 2023
Contributed by Lukas
Nature has provided us with exquisitely accurate clocks in the form of pulsars, those rapidly rotating neutron stars whose beams of radiation act like...
All Things Dark: Matter, Energy, and More
28 Jun 2023
Contributed by Lukas
Top quark has a field day in this episode with a model for fuzzy dark matter, new data that could shed light on dark energy, and a cool x-ray echo fro...
Earth's Pebble Accretion and the Boring Billion
21 Jun 2023
Contributed by Lukas
New analysis of radioisotopes of meteorites and the Earth suggest the Earth formed in only a few million years via a process called pebble accretion. ...
Supernovae Near and Far
14 Jun 2023
Contributed by Lukas
There's a bright supernova in a nearby galaxy, and a very distant supernova made brighter by the beauty of gravitational lensing. In another galaxy, a...
Is the Universe Left or Right-Handed?
31 May 2023
Contributed by Lukas
Lefty astroquark Jim Cooney leads us on an exploration of what it means for the universe to have chirality. In other words, is there a break in parity...