How do stars die? And what happens when they do? To find out, Dr. Charles Liu and co-host Allen Liu welcome Dr. Ashley Villar, who teaches astronomy at Harvard and whose team studies supernovas as they happen.

As always, though, we start off with the day’s joyfully cool cosmic thing, the release of a set of new Hubble Space Telescope images of the Crab Nebula and the pulsar at its center. Needless to say, it’s a great start to an episode about a team of scientists who actually study the moment a star explodes and the immediate aftermath.

Ashley explains how they have been able to use LIGO, the gravitational wave detector, as a sort of early warning detector that twice gave them enough time to set up their instruments to observe the explosion over the next few hours and days as it unfolds.

Professor Villar talks about how neutron star mergers and magnetars may be the source of heavy elements like gold and uranium. Or, as Chuck says, “A gold-filled smoke ring puffing off of a highly spinning, highly magnetic neutron star - what a great picture that would be.”

Ashley is looking forward to how the Vera Rubin Observatory is going to change the observation of these events. In the process of explaining, Professor Villar answers an audience question from Jamison, who asks how often stars explode in space. It turns out, in our observable universe, there’s a supernova every 2 seconds! We currently detect about 10,000 of these explosions every year - Vera Rubin will be able to detect 10,000 of these explosions in just two weeks.

In order to get a handle on this flood of data, Dr. Villar and her team will be looking for these exotic physics needles in a haystack using machine learning models to look for patterns and abnormalities and “go fishing.”

Charles asks Ashley for her take on AI and whether we should be afraid of it or not.(And yes, take the opportunity to plug co-host Allen Liu’s forthcoming book, “The Handy Artificial Intelligence Answer Book.”) Allen and Ashley discuss the difference between how a chatbot like ChatGPT operates and how she trains her models.

There was a second part to Jamison’s question about exploding stars: Are we in any danger. Dr. Villar explains that when we just look at our Milky Way, supernovas occur only once a century, so we’re not in any danger.

Next, Jessie asks, “How do we know the universe is infinite?” Our answer is, we don’t. That doesn’t stop us from discussing it, though, and the conversation takes us to, among other places, the Nazca lines in Peru and the quantum effect that creates iridescent blue butterfly wings. (You can read the scientific research mentioned in the episode here: https://www.nature.com/articles/ncomms8959)

We end with a discussion about supernovas, neutrinos, space dust, gamma ray bursts, and what kind of event it would take to interrupt the normal activities of space telescopes like the James Webb Space Telescope or the Vera Rubin and hijack them for a disruptive observation. And we get a book recommendation from Ashley, “Katabasis” by R. F. Kuang, about a grad student who journeys to hell to get a letter of reference from her deceased advisor.

If you’d like to know more about what Professor Villar is up to, you can check out her lab’s website at http://astrotimelab.com/.

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.

Credits for Images Used in this Episode:

CHAPTERS:

00:00 - Welcome to The LIUniverse

02:14 - Joyfully Cool Cosmic Thing of the Day - Hubble Crab Nebula Images

07:06 - Neutron Star Mergers, Magnetars, and Space Gold

09:18 - How Often Do Stars Explode?

12:35 - Can AI Help Us Find Supernovas?

17:11 - Are We In Danger From Exploding Stars?

19:48 - How Do We Know the Universe Is Infinite?

24:01 - How Does Quantum Physics Impact Color in Butterflies and Supernovas?

31:16 - How to Hijack a Space Telescope

How do planetary systems form? If you wanted to observe them, where would you look and what would you look for?

To find out, Dr. Charles Liu and co-host Allen Liu welcome Luke Keller, professor of Astronomy and Physics at Ithaca College, who together with his team has identified 9 of these early solar systems.

As always, though, we start off with the day’s joyfully cool cosmic thing: a recently published paper that determined that at any given time, it is likely that a couple of extrasolar objects like 3I/ATLAS and Oumuamua would be present in our solar system. The real issue is detecting them.

For context, Luke, whose science has focused over the years on finding debris from solar systems, explains how protoplanetary discs can eject matter that ends up orbiting that star. He’s especially fond of cosmic dust, “the catalyst for the formation of planets and asteroids and comets…”

Then it’s time for a question for Luke from the audience, from Elisa: “I heard that the James Webb Space Telescope sees infrared light. How does that work? Does that mean it couldn't see the Sun?”

Luke breaks down the various wavelengths of light and our Sun. He also explains how the JWST works and why it never looks at the sun.

It turns out that Luke has built a variety of astronomical instruments including imaging and spectroscopic tools with for large observatories. He’s also used information from instruments like JWST in his studies of the formation of stars and solar systems.

Luke explains how his teams search for preplanetary solar systems, what they’re looking for, and where they’re currently looking: associations of stars in the direction of the constellations Taurus, Scorpius and Chamaeleon. All told so far Luke and his team have identified 9 of these early solar systems. He then breaks down the current thinking on how planetary systems form from clouds of dust. He explains some of the processes that involves, along with the types of planets that may form.

For our next audience question, Joan asks, “What do you think is the most interesting constellation?” Luke picks two: first, Ursa Major, aka “The Big Dipper,” because he grew up in Alaska and saw it all the time – along with “auroras all the time.” The second constellation he picks is Orion, aka “The Hunter,” because it contains some of the closest star forming regions of our galaxy.

Luke unpacks the difference between “watching the sky” and “observing the sky” – and why he encourages the latter to both his students and the general public. And before the episode is over, we get to hear about Luke’s live show, Spacetime, where he collaborates with poet David Gonzalez and guitarist Álvaro Domene in a stage performance that’s equal parts astrophysics, poetry, and music.

If you’d like to know more about Luke’s show, Spacetime, check it out at https://spacetimeshow.org/.

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.

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How can a helicopter fly in space? How does LIGO detect gravitational waves? How do quantum electronic devices like Josephson junctions work? Could AI turn evil and destroy humanity? What about those grabby aliens? In this episode of Chuck GPT, Dr. Charles Liu and co-host Allen Liu answer audience questions about the technology of astronomy, astrophysics, and the future.

To read those questions, we welcome back our executive producer Leslie Mullen, community director Stacey Severn, and intern Eleanor Adams.

As always, though, we start off with the day’s joyfully cool cosmic thing: the ESA’s new Deep Space Antenna in Australia. This fourth antenna in ESA’s network will be used to manage communications for their slate of upcoming missions.

For our first audience question, Anna asks, “How is it possible that a helicopter can work in space? I heard that NASA launched a helicopter to Mars and is going to send one to Saturn in a few years.”

Leslie, who worked at JPL, talks about the Perseverance Rover and its helicopter, Ingenuity. She explains that they’re not actually flying in space, but in the atmospheres of a planet or a moon. Even so, the thin atmosphere of Mars (less than 1% of Earth’s) created unique problems that don’t exist on Earth. Leslie got to interview the inventor of Ingenuity, Bob Balaram, in her JPL podcast episode, “Flying with Ingenuity.” She describes how JPL tested the helicopter here on Earth, and what it was like the moment Ingenuity actually took flight.

The team discusses Dragonfly, the helicopter that will be flying on Saturn’s moon Titan, and how Titan’s thick methane atmosphere creates an entirely different set of engineering problems than Ingenuity faced on Mars.

Stacey reads our next question, from Joe: “Gravitational wave detectors like LIGO are said to detect changes in the length of space by less than the width of a proton. But how is that possible, if all the atoms that make up LIGO are so much bigger than protons?” Chuck explains interferometry (the I in LIGO!) and Allen offers a great analogy using a ruler.

Eleanor reads a question from TikTok, which Esmeregildo asked in response to our video about Josephson Junctions and the Nobel Prize in Physics: “What is the purpose of the insulating barrier?” Chuck’s answer takes us down a quantum tunneling rabbit hole, filled with superconductors, insulators, and quantum computing.

Diane asks: “Professor, you say that astronomers have used AI for a long time so you're not afraid of AI. But AI isn't being used by just scientists anymore, and corporations are using AI to make money now rather than to make scientific advances. So should we be afraid of AI today? Could AI turn evil soon and destroy humanity?” Allen, co-author of a soon-to-be published book about AI, offers a mostly hopeful answer, although Chuck compares AI to nuclear power and Leslie brings up real world problems AI is already creating.

Our last question from our audience is, “Hi Dr. Liu, I heard you talking about grabby aliens recently. Could you explain the concept a little more? For example, would humans be grabby aliens if we explore space and colonize Mars and we find there's life there? Would we have to destroy grabby aliens right away if we find them, or would we have to hide from them?” It’s the perfect way to end this edition of Chuck GPT!

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.

Image Credits:

CHAPTERS

03:08 - Joyfully Cool Cosmic Thing of the Day –New ESA Deep Space Antenna

07:36 - How Can the Ingenuity Helicopter Fly on Mars?

16:26 - How Can the Dragonfly Helicopter Fly on Saturn’s Moon Titan?

19:44 - How does LIGO detect gravitational waves?

26:01 - Josephson Junctions, Quantum Tunneling, and Superconductors Explained

36:00 - Could AI Turn Evil Soon and Destroy Humanity?

44:48 - Would Humans Be Grabby Aliens if We Explore Space and Colonize Mars?

#LIUniverse #SciencePodcast #AstronomyPodcast #LIGO #ArtificialIntelligence

Is universal expansion slowing? What is the Bubble Universe Theory? Will we control AI, or will AI control us? In this special Chuck GPT episode of The LIUniverse, we answer questions from the Annual Global Summit in Erie, Pennsylvania where Dr. Charles Liu gave a talk on “2050 - The Future of Humanity.”

To help ask those questions, Chuck and co-host Allen Liu welcome Stacey Severn, our Social Media Manager/Community Director; and physics student Eleanor Adams, our first intern.

As always, though, we start off with the day’s joyfully cool cosmic thing, suggested by Stacey: the recent discovery of one of the most distant and earliest known galaxies observed, existing just 570 million years after the Big Bang. It’s got a supermassive black hole 20 times the mass of ours and was found via gravitational lensing by the Canadian NIRISS Unbiased Cluster Survey (CANUCS) using the James Webb Space Telescope.

Then it’s time for the main event. Eleanor reads the first Erie audience question from William W., age 13, who asks, “In Bubble Universe Theory, is the force splitting universes apart the same force causing the expansion of the universe, also known as dark energy?”

Chuck explains Bubble Universe Theory, aka “Eternal Inflation,” and then how dark energy is different than the forces that cause expansion.

Next question: “Have you seen the latest research from South Korea stating universal expansion is actually slowing, thus reducing greatly the amount of dark matter? If it's correct, what are the implications?”

Chuck explains the current state of research around the issue, starting with the Dark Energy Spectroscopic Instrument (DESI) survey at the Kitt Peak National Observatory telescope. DESI gave indications of a change in the amount of dark energy being produced; this new study raises questions about how we measure the expansion of the universe using type 1a Supernova.

Next question: “What percentage of our global warming does science attribute to man-created activities vs. a natural progression? Even though the world is getting warmer, wouldn’t it be worse if the temperature were getting colder?”

Chuck looks at the natural progression of the increase of carbon dioxide and compares it with the larger and more rapid increase in CO2 levels since the Industrial Revolution began. As to whether warming or cooling is better, Allen says that while it’s a question of magnitude, neither extreme is desirable.

Mark M’s question is next: “Will we achieve control or effective management of AI, or will it control, or even define, our daily lives?

Allen, whose book on AI is coming out soon, says the answer is far from clear cut. He explains that while there are many efforts to ensure we maintain control, there’s no guarantee that we’ll succeed.

Next question from Erie: “How do we prepare our young children to be successful in the Age of AI?” Eleanor talks about how, like social media, you can’t stop or avoid AI, but also, like social media, parents can give their children the tools to help them use it.

Next: “Many advanced countries have declining populations, while third world countries are gaining population. How do we get tomorrow’s scientific leaders from third world education systems?”

Chuck says the best way to ensure an ongoing stream of scientific leaders is for advanced countries to continue to welcome immigrants, while Allen points out it is also important to improve the educational systems and opportunities for research in those third world countries. Stacey reminds us about the impact the internet is having on this issue.

With time running out, we squeeze in one last question from Erie: “How can the average person influence science policy in a positive direction?” Our consensus answer: people need to participate, speak out, and support others when they do, too.

We hope you enjoy this episode of The LIUniverse. Please support us on Patreon.

Credits for Images Used in this Episode:

Chapters:

00:00 - Welcome – Call Me Chuck

01:02 - Joyfully Cool Cosmic Thing of the Day – CANUCS-LRD-z8.6

08:25 - Chuck Answers Questions from Annual Global Summit, Erie, PA

09:58 - Bubble Universe Theory and Dark Energy

14:17 - Is Universal Expansion Is Slowing?

19:30 - Global Warming

27:28 - Will We Control AI or It Will Control Us?

30:14 – How Can We Prepare Our Children To Succeed in the Age of AI?

36:28 - Where Will Future Scientific Leaders Come From?

42:09 - How Can Individuals Influence Science Policy?

How do supermassive black holes actually form in the early universe? Is the Cosmological Constant not so constant after all? And what would be on the astrophysical menu at a Cosmic Brunch? To find out, Dr. Charles Liu and co-host Allen Liu welcome astrophysicist Thresa Kelly, who is a second year grad student working on her PhD at the Rochester Institute of Technology.

As always, though, we start off with the day’s joyfully cool cosmic thing, one of the recent studies made using the Dark Energy Spectroscopic Instrument, aka DESI, located at Kitt Peak National Observatory near Tucson, Arizona. According to the DESI team’s research, there is a about a 95% chance that the dark energy levels in the universe have changed over cosmic time. This “Dynamical Dark Energy model” offers the first, tiny hint that the Cosmological Constant may not be so constant after all.

Thresa, who is using DESI and other sources for her work putting together a catalog of AGNs, or active galactic nuclei – the supermassive black holes found at the center of galaxies, tells us about what DESI is trying to do and why it’s so important. The end goal of Thresa’s project is to estimate the black hole masses of AGNs, and she’s gotten spectra data on over 2,000 objects that have been observed using DESI. Thresa can’t get into the details of her catalog, which hasn’t been published yet and includes about 14,000 objects, but Allen and Chuck join her in a discussion of what’s going on with black hole masses, accretion discs, Eddington Luminosity, black hole growth, galactic evolution, and more.

Our first audience question comes from Kathryn, who asks, “When we look through a standard telescope looking at "past" versions of planets/stars/etc., how far back in the past are we observing?” Thresa explains how we use red shift to measure how long light from a galaxy takes to reach us to help us determine how far in the past the objects are. For instance, an AGN with a red shift of 7 can reach back to the period of “Cosmic Dawn” or, as Thresa puts it, “Cosmic Brunch” taking place 12 billion years ago.

Thresa talks about her experience in an REU, or “Research Experiences for Undergraduates,” funded by the NSF, which enabled her to spend time studying at the University of Hawaii and cemented her desire to go to grad school, get a PhD, and become a “real scientist.” She explains how each step of her career brought her from Kansas to where she is today.

Our next audience question comes from Walter: “If a quasar's jets are aimed directly away from Earth, would we then not be able to see the supermassive black hole?” Thresa says that depends on how you define “seeing” a black hole, and that even without visible light, you can discern black holes by looking at other wavelengths like x-rays and ultraviolet rays which are generated by different component areas of the black hole like the corona, accretion disk, or the torus.

Chuck notices a shelf of games behind Thresa and asks her about them. She pulls out Stardew Valley, a farming simulator she plays with her fiancé and her fellow grad students. It’s not long until Chuck, Allen and Thresa are geeking out about Dungeons and Dragons.

Finally, Chuck asks Thresa to speculate on a specific scientific discovery that may come out of her PhD thesis work. Her answer: figuring out how supermassive black holes actually form in the early universe.

If you’d like to know more about Thresa Kelly, you can find her on LinkedIn.

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.

Credits for Images Used in this Episode:

What were our joyfully cool cosmic things of 2025? To find out, Dr. Charles Liu and co-host Allen Liu welcome three members of The LIUniverse production team: Jon Barnes, our Editor and self-proclaimed “#1 LIUniverse Fan,” Stacey Severn, our Social Media Manager/Community Director, and physics student Eleanor Adams, the show’s first intern.

Unlike nearly every episode so far, this time, rather than limit ourselves to one joyfully cool cosmic thing, the team is going to each share their individual joyfully cool cosmic things of 2025. Chuck’s saving his for later, so instead, we’re just going to jump right into everyone’s favorite “cosmic thing of the year”, starting with our co-host, Allen Liu.

Allen picks the Vera C. Rubin Observatory and the Legacy Survey of Space and Time (LSST). Allen and Chuck, who is also on the Rubin’s Science Advisory Committee and has been involved in the development of the Observatory for over a quarter century, discuss how truly amazing the images are in terms of detail and resolution.

Allen shares that he’s most excited to see images of transients like asteroids and gravitational lensing, since the Rubin will be taking images of the same areas twice with a gap of one week. Chuck talks about the citizen science aspect of the Rubin and encourages each of you in our audience to try and discover something on your own.

We hear about some of Allen’s published papers, including one on using VR for scientific research. The group talks about VR (including Beat Saber) and Jon shares his experience using VR technology to record his senior project at the Harold Ramis Film School at Second City, and the difficulty he had with the audio.

For Eleanor, this year’s cool cosmic thing was highly personal: her studies in modern physics this year, learning more than ever about what we don’t know, like the gap between classical and quantum physics! As she puts it, “the matter-antimatter asymmetry…broke my mind.” She also shares a little inspiration from Cal Sagan’s Cosmos.

Stacey’s cosmically cool thing of the year is relatively current: Comet C/2025 K1 ATLAS, which recently broke into 3 parts. The team compares this with the breakup of all breakups: Comet Shoemaker-Levy 9, which broke up in 1994 on its way to a collision with Jupiter.

Jon’s joyfully cool cosmic year end thingamabob is about the new science fiction show Pluribus created by Vince Gilligan (Breaking Bad, Better Call Saul), and he’s got a question for Chuck. How long would it take a signal like the one in Pluribus to travel from a star 600 light years away, like Betelgeuse or Antares? Without dropping any spoilers, the team ponders why an alien race would have reached out to Earth based on what they might have seen around the time of Charlemagne, and whether being subsumed in a hive mind would be good or bad.

This is a bittersweet episode, though, because we officially bid farewell to the show’s long time editor, Jon Barnes, who is moving on to a gig as a full-time content creator for a meal prep company that will involve lots of Jon cooking and filming himself while he does.

Finally, it’s time to wrap up the episode with Chuck’s Picture of the Year, which is related to the Vera C. Rubin Observatory, but not in a way you might expect. It’s a photo of Vera Rubin when she was 10 years old. As Chuck puts it, “Who would have known that 25 years later, she would change our understanding of the cosmos itself?”

Happy New Year from The LIUniverse crew!

If you’d like to know more about what Jon’s up to post-LIUniverse, you can check out his TikTok @iheartjonbarnes.

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.

Credits for Images and Music Used in this Episode:

#LIUniverse #AstronomyPodcast #CometC2025K1ATLAS #CometShoemakerLevy9 #VeraRubin

Are Coronal Mass Ejections dangerous to life on Earth? When are we finally going to plunge through the sulfuric acid clouds to measure the atmosphere of Venus. And what’s up with 'Oumuamua and 3I/Atlas? To find out, Dr. Charles Liu and co-host Allen Liu welcome astrobiologist Dr. David Grinspoon, aka Dr. FunkySpoon.

As always, we start with the day’s joyfully cool cosmic thing: the arrival at Earth of two consecutive Coronal Mass Ejections on Nov. 11, 2025, creating an amazing display of Northern and Sothern Lights. In the US, aurora were seen as far south as Texas and even Central America, and yet Chuck, Alan and David were all frustrated by clouds in their own attempts to see them! Luckily, they’ve each already seen auroras with their own eyes, a viewing event David likens to seeing a total solar eclipse. David discusses how solar flares can impact human technology, but that while solar flares from other stars could be dangerous for life on their planets, at this point in our sun’s lifetime, they are unlikely to wipe out life on Earth. Chuck shares aurora images that were taken by our previous guest, astrophotographer Elliot Severn.

For our audience questions this week, we’re answering questions given to Chuck while he was presenting at an event in Erie, PA.

The first question Chuck asks David is, “When we have interstellar visitors like 'Oumuamua and 3I/Atlas, [1] why are they moving so fast in our space? They seem to defy gravity [2] How can they know what 3I/atlas is made of but not the density or materials?” David explains why the extreme speed at which they are moving is actually proof that they are interstellar objects and not something else. He also discusses how we use spectroscopy to determine what they’re made of the same way we determine what distant stars and exoplanets are made of.

Our next question from Erie, PA is, “Is there a mathematical probability or formula to predict the likelihood of life existing int he universe? In other words, has someone developed a model to predict how many unique things need to happen for life to evolve?” David explains the Drake Equation, a series of questions that help astrobiologists assess the probability of intelligent life in the galaxy.

Our last question from Erie is, “If humans find life on a different planet, would we actually understand how to coexist with the information, or will world leaders hide the truth from us?” David points out – as someone who has helped devise astrobiology policy – that the response depends in part on the specifics of the discovery, like how far away that life is. But would the government be able to hide it? David says that the scientists who discover it would be shouting it from the rooftops: “How long would it take to type it and hit send?” And as Chuck points out, the very act of the government trying to censor it would turbocharge the speed at which scientists would get the news out.

The real problem, David says, is the potential of each discovery being overhyped by journalists, leading to public burnout. He brings up two examples of overhype: the discovery of possible biosignatures in iron nodules on the Martian rock Cheyava Falls in 2024 by the Perseverance Rover, and the presence of dimethyl sulphide in the atmospheric composition of exoplanet K2-18 b.

Next, we turn to David’s “second favorite planet,” Venus, which he has studied and written about extensively. David shows us the first book he ever wrote, “Venus Revealed” and talks about upcoming missions to Venus: two from the US, DAVINCI and VERITAS; a European Space Agency mission named EnVision; a Venus Orbiter Mission by India’s ISRO, and a private Rocket Lab mission to Venus. David, who is involved with the DAVINCI mission, tells us about the plan to plunge through the sulfuric acid clouds to measure the Venusian atmosphere and surface with modern instruments for the first time.

We end with a discussion of the anti-science cycle we’re going through, and David shares why he thinks this moment is so unusual and scary, but also why there is reason for hope. Chuck talks about why scientists take the long perspective, and David reminds us of the huge worldwide support for the exploration of space.

If you’d like to know more about David, you can check out his YouTube channel @DrFunkySpoon, or @DrFunkySpoon on Blue Sky and Instagram.

We hope you enjoy this episode, and, if you do, please support us on Patreon.

Image Credits:

#LIUniverse #CharlesLiu #AllenLiu #SciencePodcast #AstronomyPodcast #DavidGrinspoon #DrFunkySpoon #Oumuamua #3IAtlas #InterstellarObjects #CoronalMassEjections #aurora #solarflares #DAVINCI #VERITAS #EnVision #antiscience #spaceexploration

How do planetary ring systems rings form, and what keeps them in line? What exactly is the Dragon Cloud of Saturn? And what’s up with quasi moon 2025 PN7? To find out, Dr. Charles Liu and co-host Allen Liu welcome Cornell University’s dynamical astronomer Dr. Phil Nicholson for a refresher course in orbital mechanics.

As always, though, we start off with the day’s joyfully cool cosmic thing, which is right up Phil’s alley: the recent discovery of quasi moon 2025 PN7. Phil unpacks the orbital mechanics to explain the critical differences between quasi moons and regular moons, and also 2025 PN7’s strange relationship to Earth’s orbit. He also explains the dynamics of the sun’s tidal forces and Earth’s Hill Sphere.

For our first question from the audience, Jameson asks, “Are meteorites smaller copies of planets. Are all of them the same?” Rather than discuss meteorites, which are the tiny survivors that have crashed on Earth, Phil pivots to where many of them come from in the first place: asteroids. Really big asteroids share some characteristics with planets, like being spherical in shape, whereas the smaller ones can be highly irregular, like the dumbbell-shaped asteroid 216 Kleopatra, or Arrokoth, previously known as Ultima Thule. Chuck asks Phil about the different shapes large asteroids can come in, and Phil points out 433 Eros, the second largest Near Earth Object, which is banana shaped.

The ensuing brief discussion of the “is it a long, skinny asteroid or an interstellar starship?” debate, like the one sparked by Oumuamua, leads to a conversation about Arthur C. Clarke’s “Rendezvous with Rama”, which described just such a starship back in 1973. Somehow, we end up looking at the “face” on Mars and the “Death Star,” aka, Saturn’s moon Mimus as it was imaged by the Cassini spacecraft.

Phil actually worked on the Cassini mission, and Chuck asks him to talk about his experience peering hundreds of miles deep into Saturn’s atmosphere with the spacecraft’s Visible and Infrared Mapping Spectrometer (VIMS). Along with other instruments run by other teams, the mission changed our perception of Saturn’s “boring” atmosphere, documenting aurora, lightning, and giant storms like the “Dragon Cloud of Saturn.”

Our next student question comes from Marvin, who asks, “What exactly is a Shepherd moon?” To answer, Phil describes what Saturn’s rings are made of, how they form, and how they’re structured. He explains what happens when particles that make up the rings collide, why some rings spread over time, while others stay very narrow, and the role Shepherd satellites play in the process.

We end with Chuck soliciting a few classic sci-fi recommendations from Phil, who suggests anything by Arthur C. Clarke, the Foundation Trilogy by Isaac Asimov, and almost anything by Larry Niven, including Ringworld, his most famous series.

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon at https://www.patreon.com/theliuniverse.

Credits for Images Used in this Episode:

#LIUniverse #CharlesLiu #AllenLiu #SciencePodcast #AstronomyPodcast  #DynamicalAstronomy #PhilNicholson #OrbitalMechanics #Rings #SpaceStorms #QuasiMoons #2025PN7 #HillSphere #433Eros #Asteroid #216Kleopatra #Arrokoth #UltimaThule #Cassini #VisibleAndInfraredMappingSpectrometer #VIMS #DragonCloudOfSaturn #ShepherdMoon

Can an ultra-compact dwarf galaxy have a supermassive black hole at its center? Are there galaxies with supermassive black holes that are offset from their galactic centers? To find out, Dr. Charles Liu and co-host Allen Liu welcome “the other” Dr. Matt Taylor, an Assistant Professor of Astronomy at the University of Calgary, who joins us from the control room of the largest astronomical telescope in Canada, at the Rothney Astrophysical Observatory (RAO) in Alberta, Canada.

As always, though, we start off with the day’s joyfully cool cosmic thing, which starts with the discovery of a supermassive black hole in the middle of an ultra-compact dwarf galaxy M60-UCD1 located in the Virgo galaxy cluster. That led to the discovery of more 4 UCDs in the Virgo Galaxy Cluster and 1 in the Fornax galaxy clusters, but then the limits of technology prevented the discovery of any additional UCDs. But now, by using the James Webb Space Telescope, Matt and his fellow researchers (including Dr. Vivienne Baldassare, our former guest for Black Holes and Space Junk with Vivienne Baldassare) have just published a paper about their discovery that in the smallest, lowest mass UCD yet found, they found a roughly 2,000,000 solar mass black hole. Basically, that’s a tiny galaxy to hold a supermassive black hole, and Matt is sure there are many more of these waiting to be discovered.

After that Matt tells us about his atypical journey to astronomy, including his first career – as a professional chef. When cooking stopped being fun, Matt enrolled at a local community college and “moved from gastronomy to astronomy” as Allen puts it.

Our first audience question comes from our Patreon Patron Taylor L, who asks, “Is it possible dark energy and the acceleration of the universe's expansion could be explained by the idea that the black hole we live in is constantly devouring matter from outside?” Matt passes on determining whether or not we live inside a black hole. But, he explains that while at the galactic level expansion is happening on a really large scale, at a smaller scale like our local group of galaxies (Milky Way, Andromeda, and local dwarf galaxies), our mutual gravitation counteracts that expansion.

Matt goes on to discuss how accretion disks are what makes it possible to “see” a black hole, but that ultra-compact dwarf galaxies don’t have gas and dust forming accretion disks. Instead, they use stellar velocities to find black holes in UCDs.

Next up, Matt tells us about some of the research he’s doing into archetypal compact elliptical (cE) galaxies, which have the mass of a giant galaxy put into the volume of a dwarf galaxy, and how black holes appear in these systems. And Matt dangles another upcoming paper about galaxies with supermassive black holes that are offset from their galactic centers.

For our next audience question, Pshemo asks: “We often say gravity is weak compared to other forces. But in the right regimes, like near black holes and neutron stars, or on large cosmic scales, it dominates every other interaction. Should we stop calling gravity a weak force?” It’s a thought-provoking question with an even better answer, so please watch or listen to the episode to hear it yourself from Matt.

If you’d like to know more about Matt, you can check out his website, mataylor5128.github.io. (The 5128 comes from the famous and very cool galaxy NGC 5128, aka Centauras A)

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.

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How do very small galaxies form? What’s going on inside them? And what happens when black holes collide? To find out, Dr. Charles Liu and co-host Allen Liu welcome astrophysicist and “Galaxy Detective” Dr. Charlotte Olsen from New York City College of Technology – and you can call her Chuck, too!

As always, though, we start off with the day’s joyfully cool cosmic thing, the latest announcement from LIGO about the detection of a gravitational wave event in 2023 from the loudest collision we’ve heard so far. In this case, the wave was caused by the collision of two black holes that created one new black hole about 60x the mass of our Sun and released an entire sun’s worth of energy. Charlotte explains why there are many black hole collisions going on, and how LIGO detections are now being combined with data from other gravitational wave detectors to give us more precise measurements.

You’ll also hear about Active Galactic Nuclei (AGNs) and their negative impact on Charlotte’s research. Charlotte talks about what she looks for in her research, and why it all comes down to “wanting to see more photons” to better validate her modeling.

Our first question from the audience comes from Joe, who asks, “What does it mean for the Milky Way to have a bar? Why does it have a bar? And how can such a long bar form?” It turns out that many spiral galaxies like ours have bars, and Charlotte explains a little about bar structure. She brings up the current debate about the stability of these bars, and points out that they actually come in slightly different configurations and that star formation at the ends of the bar has an impact, too. Unlike previous thinking, these bars can develop earlier in galactic evolution and can last a very long time. In other words, as Charlotte puts it, “The bar is always open.”

Next, Chuck asks what got Charlotte into astronomy. She describes the inspiration she drew from both the dark skies of Northern California, where she grew up, and from the science fiction she read. She shares a few of her “million and one jobs” she did, including her stint as a bassist in a band.

That tees up our next audience question, from Shivani, who asks, “How do you mix music and science? I can't decide if I want to be a scientist or a musician someday – can I be both?” Yes, Charlotte says, and explains why doing both might actually be better. She talks about the value of music, and passion, and hobbies that are more than just hobbies, as well as some of the live music she’s been seeing in Brooklyn, Long Island and Queens.

Finally, Chuck asks Charlotte about the current passion project she’s working on. She tells us how she’s looking at a handful of galaxies in multiple wavelengths and comparing them to each other to figure out “what’s going on under the hood.”

If you’d like to know more about Charlotte, you can connect with her on Bluesky at @charlotteeureka.bsky.social or on her GitHub page charlotteolsen.github.io.

We hope you enjoy this episode of The LIUniverse, and, if you do, please support us on Patreon.

Credits for Images Used in this Episode:

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