If a black hole shreds a star and nobody is around to hear it, does it make a sound? To find out, Dr. Charles Liu and co-host Allen Liu welcome Professor Yvette Cendes, (aka u/Andromeda321 on Reddit), a Radio Astronomer studying transient radio signals from space.

As always, though, we start off with the day’s joyfully cool cosmic thing, a report by the Dark Energy Survey that seems to show that the amount of dark energy originally described as the cosmological constant by Albert Einstein might in fact be variable. As Prof. Cendes explains, the data indicates that universal expansion is still accelerating but the rate might be changing.

After Yvette explains what she does, and how radio astronomy works in concert with optical astronomy to deliver a more complete understanding, Chuck asks her to explain Tidal Disruption Events, or TDEs, about which she’s a world expert. A TDE is when a star wanders too close to a supermassive black hole and ends up getting shredded. Yvette prefers to call them “Shredders.”

Our first audience question comes from Nachama, who asks, “When will the black hole in the Milky Way eat the Sun?” The good news, according to Yvette, is that will never happen. As she explains, black holes actually don’t suck any more than anything that massive would, and we’re 25-30,000 light years away from Sagittarius A* – too far away to worry about.

Next, Chuck asks Yvette about one of the most famous transient signals we’ve ever found, the so called “Wow!” signal detected in 1977 by Jerry Ehman at the now-defunct Xavier Observatory in Ohio. Because the signal looked exactly like what might be expected if it were of extraterrestrial origin, Ehman circled it on the printout and wrote, “Wow!” Unfortunately, it never repeated. The most likely explanation, according to Dr. Cendes, is that it was some sort of manmade interference, although the signal is currently being reinvestigated.

Yvette recounts how she ended up ended up as a first-term professor at the University of Oregon after studying in the Netherlands and Toronto and working at Harvard. Then she answers an audience question from Yan Min, who asks, “Where is the best place in the world to study astronomy? I live in New York – Is it New York?” Unfortunately for Yankees fans, Yvette says it would most likely be Cambridge, Massachusetts thanks to Harvard, which has the biggest number of astronomers under one roof and operates the Chandra X-Ray Observatory, and M.I.T. on the other side of town if you get bored.

Chuck asks Yvette what happens after a black hole shreds a star. Shredders, she explains, are rare. In our own Milky Way, they probably happen once every million years. Once a TDE is classified by optical astronomers, Yvette and her team point their radio telescopes at the tidal radius outside of the event horizon to discern the outflows weeks, months and even years after the initial event.

He also asks Yvette if she has any hobbies to help her decompress from thinking about violent events in the universe. She likes to cross stitch, the “original pixel art.” Yvette shows us a cross stitch she made of the James Webb Space Telescope complex mirror, another featuring an 8-bit Mario screen with the words “What doesn’t kill me makes me smaller,” and a third with objects in the Solar System. She also embroiders and shows us a hoop featuring the constellations visible in the northern hemisphere night sky.

We end with Yvette and Allen schooling Chuck about Reddit’s immense reach and value in scientific discourse. One subreddit, called r/Space, has “27 million intelligent lifeforms” subscribed to it. On Reddit, Yvette’s username is u/Andromeda321, and she’s one of the top users on the platform over 1 million karma points. She’s known for starting her posts that explain or comment on recent discoveries with the phrase, “Astronomer here!”

If you’d like to follow Dr. Yvette Cendes, you can find her on Reddit, where she’s u/Andromeda321, and her dedicated subreddit, reddit.com/r/Andromeda321. You can also follow her on Bluesky @whereisyvette.bsky.social.

Links to the astronomy cross stitch kits shown in the episode:

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

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#liuniverse #charlesliu #allenliu #sciencepodcast #astronomypodcast #yvettecendes #andromeda321 #astronomerhere #radioastronomer #transientradiosignals #darkenergysurvey #cosmologicalconstant #universalacceleration #wow!signal #6equj5 #tde #tidaldisruptionevents #supermassiveblackhole #shredders #sagittariusa #milkyway #crossstitch

Why is it so difficult to study the evolution of early galaxies? Are metallic D&D dice better than plastic ones? And can you have too many Pokémon tattoos? To find out, Dr. Charles Liu and co-host Allen Liu welcome Justin Cole, who is currently a grad student at Texas A&M studying the evolution of distant galaxies in pursuit of his PhD in Astronomy and Astrophysics.

As always, though, we start off with the day’s joyfully cool cosmic thing – the recent – and remarkable – discovery of four planets orbiting Barnard’s Star, a tiny star not much bigger than Jupiter with the highest measured proper motion of any star in our sky. Chuck and Justin discuss why the discovery of new exoplanets is so challenging, which leads to Justin explaining what he’s studying: galaxies in our universe that developed less than 1.5 billion years after the Big Bang – about 2.5 billion years before the birth of our own Milky Way Galaxy.

We’ve got a handle on what’s going on with our neighbors like the Andromeda Galaxy, but when it comes to early galaxies, we have a very limited range of wavelengths and scant data to study. This makes it harder to derive understandings of galactic evolution and whether they support or conflict with the standard model of physics.

Our first audience question comes from Ricardo, who asks, “What if we discover extraterrestrial plant life and find out it’s intelligent? Actually, what if we discover plants on Earth are intelligent? Would it be unethical to eat them?” After Chuck shares a little about Marvel’s intelligent, telepathic species of plants called the Cotati, and imitates Audrey 2 from Little Shop of Horrors, Justin weighs in on the ethics of eating intelligent plants and asks a critical question: Would we understand them enough to know? What would happen if we bit into a head of alien lettuce and it started screaming? The ensuing discussion is… tasty, albeit a little unsettling.

Our next question is from Thomasina, who asks, “I read that the Big Bang theory is in trouble – what does that mean? And did the Big Bang never happen?” Justin, who is an early universe guy, clarifies what’s going on here. We occasionally find galaxies that seem to be too big for the amount of time that they’ve had to grow. We’re also finding black holes that with our current instruments, also appear to be too big. In each case, we’re finding better ways to simulate these situations, and it’s not that they’re too big, or that the Big Bang isn’t supportable, it’s that we’re using tools that are calibrated to “nearby and today” that aren’t as good at helping us assess early galaxies.

Next up, Justin, who is getting ready to run a Dungeons & Dragons 5th Edition roleplaying session after the podcast recording, talks about using D&D Beyond to create his own campaigns (set in the World of Warcraft universe!). Chuck and Justin discuss the benefits of rolling metal dice, and Justin shows off a couple of his beautiful D20. Not to be outdone, Allen shares his 120-sided die, the largest die allowed by three dimensional Euclidean geometry in conventional space. Meanwhile, Chuck tells us the sad story of his old, worn plastic dice. As Allen points out, Chuck was in the hobby before it was cool! And as we run out of time, Justin shares his intention to get one Pokémon tattoo for every state he and his wife visit.

If you’d like to know more about what Justin’s up to, he suggests you Google “Justin Cole Astronomy” or “Justin Cole A&M.”

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

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#TheLIUniverse #CharlesLiu #AllenLiu #SciencePodcast #AstronomyPodcast #JustinCole #Astronomy #Astrophysics #BarnardsStar #GalacticEvolution #BigBang #StandardModelofPhysics #ExtraterrestrialPlantLife #IntelligentLife #D&D #Pokemon #Tattoos

What’s it like to stand at the edge of human knowledge, where we don’t know what leap forward in understanding the next technological innovation will herald? To find out, Dr. Charles Liu and co-host Allen Liu welcome Dr. Melodie Kao, resident radio astronomer at the Lowell Observatory in Flagstaff, AZ, where Clyde Tombaugh discovered Pluto back in 1930. (And if you’re scratching your heads saying, “What’s a radio astronomer doing at an optical observatory?” you’re not alone. Short answer: Melodie convinced them they wanted one, and that it should be her!”)

As always, though, we start off with the day’s joyfully cool cosmic thing, the amazing discovery by the NEID Spectrograph at the WIYN telescope at Kitt Peak Observatory of a planet 9 times the mass of Earth orbiting a sun-like star 49 light years away with an orbital period of just 31 days. Melodie explains the precision of the measurement required to discover a planet at that distance, and shares one of her own recent discoveries using a technique called very-long-baseline interferometry (VLBI). In a groundbreaking effort she strung together 39 radio dishes across the northern hemisphere of Earth in a multi-observatory effort to create an Earth-sized telescope (similar to the technique that was used to create the first image of a black hole) and pointed it at a brown dwarf and measured its magnetic fields and radiation belts (like our Van Allen belts). For comparison, the effort was like measuring a pea perched on the Golden Gate Bridge in San Francisco while standing on the Statue of Liberty in NYC.

The trio discusses the importance of the discovery of the Van Allen belts, and how that allowed us to plot trajectories that avoided the worst of that radiation for Apollo astronauts on their journeys to the Moon.

For our first audience question, Ari from North Greene High School in Tennessee asks, “What is the percentage of possible exoplanets that are similar to the earth’s atmosphere, placed in their solar system (within a similar area of their respective Goldilocks zone), gravity, etc.? And how long would it take to hypothetically get to them?”

That turns out to be a very complicated question, and Melodie knows someone who has devoted her entire career to answering it. It’s one of the questions that drove the creation of the James Webb Space Telescope and is the basis of the Drake Equation. The bottom line, though, is that we don’t know yet, and until we find a rocky planet with an Earthlike atmosphere orbiting a sun-like star outside of our solar system, it will remain unanswerable.

Next, Charles asks Melodie how she became an astronomer, especially since she’d always planned on being an architect. She even went to MIT to become one, but she missed studying physics, which she realized she truly loved. MIT had just finished constructing their Center for Theoretical Physics, and Melodie shares the story of how she convinced MIT to bend the rules and let switch her major to Physics while continuing to study architecture. When she attended a lecture by a grad student about galaxy clusters, and learned how you could back out the formation history of a cluster of galaxies by looking at the gradients of colors generated by starlight, she realized astronomy was a way to unlock the secrets of the universe.

Our next question comes from Alex at North Greene: What are the conditions necessary for life in the universe? It’s a question without an easy answer, but the conversation it spawns is worth your time to listen to. It leads Melodie to talk about her love of exploring the natural world and how she co-created a Wilderness Astronomy class. She’s also a guide for off-trail, high route backpacking trips where you don’t know what’s coming next and you need to rely on your instincts, curiosity and bravery as you explore the world, and the universe, around you.

If you’d like to know more about what Melodie is up to, she’s not on social media but you can check out her website. You’ve also got an invitation to visit her at the Lowell Observatory for a personal tour!

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

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What will well-dressed astronauts be wearing on the Artemis III mission? Will AI destroy creativity? Can we actually make leather clothing out of mushrooms?

To find out, Dr. Charles Liu and co-host Allen Liu welcome engineer and futurist Alexia Stylianou, who is designing wearable biometric platforms that can measure human biomechanics to a resolution and degree far beyond what’s accessible to everyday people.

Before we get to introducing our guest this episode, though, Charles whets our appetite about amazing developments coming out of the Vera C. Rubin Observatory where he’s on the Science Advisory Committee.

Our joyfully cool cosmic thing of the day is Firefly Aerospace’s Blue Ghost Mission 1 to the Moon. As Allen points out, it’s part of NASA’s CLPS (Commercial Lunar Payload Services) initiative and is the most successful private Lunar landing to date – among other things, it landed right-side up! Alexa talks about the importance of giving engineers the freedom to solve problems and the uncertainty of programs like this continuing to be funded by NASA. Allen brings up the Viper, a NASA-funded lunar rover which was built, but lost its funding before testing was completed.

Charles asks Alexia to tell us about an example of something on the horizon she thinks is really cool, and she mentions that Prada is designing the space suits for the Artemis III mission in partnership with Axiom Space. She explains that Prada has a history of using cutting edge materials and design that makes them an appropriate partner in the process.

Then it’s time for our first audience question. Luis asks, “What is needed to create the next amazing space technology that will break all the conventions we have about space travel?” Alexia talks about the increasing importance of incorporating user-centered design or human-centered design, and how it’s revolutionizing the process. You’ll hear about the development of direct pressure space suits, as well as research into exoskeletons for use in industry and auto manufacturing – although sadly, Alien-style exoskeleton loaders like Ripley uses are still science fiction, for now.

Looking even further out, Alexia talks about nuclear semiotics – the effort to come up with ways to communicate to societies that will exist hundreds of thousands of years in the future the danger of radioactive material we’re creating now? You’ll find out why the skulls and crossbones and other danger iconography we use now aren’t up to the task, and the universality of stick-figure iconography.

Our next question comes from Johanna: “Will AI destroy creativity?” Questions like this are becoming more frequent, especially in areas like education. Chuck, Alexia and Allen jump into a thought-provoking conversation, and how there are ways to let students use AI as a tool like a calculator while simultaneously incentivizing and stimulating their creativity.

Speaking of creativity, Chuck asks Alexia about her love of science fiction and the well-designed stack of books behind her (sorry, Podcast People!). She pulls out and describes “Gideon the Ninth,” the first book in a sci-fi fantasy series about immortal space necromancers by Tamsyn Muir. Alexia talks about speculative fiction and speculative design, and tells us about a team of designers that have created a room that smells like the pollution of the future in order to offer a tangible way to engage our senses now about a future we might yet be able to avoid.

Finally, Chuck asks Alexia for one more cool futuristic development she’s wants us all to think about. She tells us about the development of mushroom leather (aka mycelium leather), an alternative, eco-friendly, and ethical textile made from fungi grown on apple waste.

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

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

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What is a transiting brown dwarf, why are they so rare, and how do you find them? Equally important, how do you make a good French macaron? To find out, Dr. Charles Liu and co-host Allen Liu welcome astronomer and astrophysicist Dr. Theron Carmichael.

As always, though, we start off with the day’s joyfully cool cosmic thing: a recent paper in the Astrophysical Journal possibly linking a supernova that took place millions of years ago and bombarded Earth with cosmic rays and radioactive iron with a flurry of virus mutation that took place in deep ancient lakes on our planet. After Theron brings up the Chicxulub meteor impact (the one that spelled trouble for dinosaurs) and how astronomical events can affect the evolution of life here on Earth, we naturally turn to the effects of extreme radiation events and… the mighty Marvel mutants themselves, the X-Men!

Then it’s time to talk about Dr. Carmichael’s bread and butter: detecting and categorizing transiting brown dwarfs, an exceedingly rare form of the “failed stars” which actually orbit other stars. Theron explains that while we know how stars and planets form, we don’t exactly understand the formation of brown dwarfs, which exist in the gray region between a star and a planet. Allen reminds us how protoplanetary discs form, while Theron points out that the distinctions may not be as clear as we used to think.

Our first student question comes from Ani, who asks, “There are a lot more small, faint stars than big bright stars. Does that mean there are a huge number of brown dwarfs in the galaxy?” Yes, according to Dr. Carmichael. And not only are there more of them, but Theron explains that they last longer, too. Finding them is challenging, but it’s become easier thanks to TESS, the Transiting Exoplanet Survey Satellite mission that’s been running for over 7 years, well past its operational lifespan.

Our next student question comes from Josie, who asks, “Could there be life on brown dwarfs?” While brown dwarfs are colder than stars, they are still too hot to form and sustain the molecules we believe are necessary for life. And while those molecules are in fact present in the atmosphere of brown dwarfs – along with titanium oxide clouds – the pressure and temperature conditions of brown dwarfs make life as we know it unlikely. Theron explains that the atmospheric conditions of brown dwarfs are not dissimilar to Jupiter, as opposed to those on Jovian moons like Europa that we’re going to explore when the Europa Clipper reaches its destination in 2030.

After that, Theron tells us about the annual MIT Mystery Hunt, his long-time love of baking, and the astronomical value of macarons. (For his French macaron recipe, please visit our Patreon page.) Allen shares how he has made cookies conforming to the Einstein tile, and Charles mentions a few scientists who also love to bake. Theron explains how baking and brown dwarf research use the same parts of his brain. We even get to see a video clip of him making macarons!

To end the show, Theron tells us about the international working group he helps lead focused on learning more about transiting brown dwarfs.

If you’d like to know more about Dr. Theron Carmichael, you can follow him on Twitter/X @TherBaer or his website, www.theroncarmichael.com.

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

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#TheLIUniverse #CharlesLiu #AllenLiu #SciencePodcast #AstronomyPodcast #TheronCarmichael #Chicxulubmeteor #BrownDwarf #protoplanetarydisc #TESS #EuropaClipper #exoplanets #EinsteinTile #macaron #failedstars #Jupiter #Europa #MITMysteryHunt

What can the history of science tell us about the world we live in today and where we might be headed tomorrow? To find out, Dr. Charles Liu and co-host Allen Liu welcome historian of science Rebecca Charbonneau, PhD from the American Institute of Physics and the National Radio Astronomy Observatory with expertise in radio astronomy and the search for extraterrestrial intelligence (SETI).

This episode kicks off with Allen and Chuck talking about January’s Lunar Occultation of Mars. You can see a photo taken by Chuck on our YouTube Community tab.

And then it’s time for today’s joyfully cool cosmic thing: a recent paper in the Astrophysical Journal Letters confirming there are galaxies that were fully formed just 400 million years after The Big Bang. Chuck, who studies galactic evolution, tells us why this changes our understanding of galaxy formation. Rebecca talks about how new ideas can be controversial and how personalities, politics and cultures can impact the evolution of science. She brings up the current controversy in astronomy concerning the locations of terrestrial telescopes and the tension between scientific and cultural imperatives. She also recounts seeing people in Russia wearing NASA t-shirts and explains how NASA understood the importance of controlling the narrative, even inviting Norman Rockwell to popularize the space program.

Our first question comes from Pablo P. on Patreon, who asks, “Can humanity be destroyed by AI powered by quantum computing?” Rebecca explains how during the Cold War, scientists on both sides engaged in “science diplomacy” that helped lower tensions. She applies this thinking to AI, pointing out that while a “Terminator-like” scenario is unlikely, public concern is causing the tech world to confront and grapple with real threats from AI like biases in hiring algorithms.

Allen, a mathematician who writes about AI professionally, addresses whether AI powered by quantum computing is more dangerous than AI in general. Rebecca shares the terrifying story of a Soviet nuclear submarine and the US navy during the Cuban Missile Crisis that nearly started a nuclear war. The dissenting actions of a single officer named Vasily Arkhipov made the difference, and she wonders if AI would have made the same decision based on the available data.

For our next question, we return to our Pablo P. from Patreon for his follow up: “How [do] we answer the question about whether or not we are engaging in self-destructive behavior?” Chuck and Rebecca discuss the confluence of astronomy and the military, and how the history of the SETI program highlights their shared concerns. You’ll find out what the Drake Equation has to do with concepts like The Great Filter. Science, she reminds us, is a tool to try to get closer to the truth, but it’s not always perfect in pointing out whether what we’re doing is safe or potentially self-destructive.

Then we turn to Rebecca’s other big passion, art history and the window into the human experience that art provides. Charles brings up The Scream by Edvard Munch and the fact that it’s actually a depiction of a real atmospheric event. Rebecca talks the use of fractal studies to determine the authenticity of Jackson Pollock art. She also explores the artistic value of scientific artifacts like the controversial plaque attached to Pioneer 10 depicting a naked man and woman, and the interstellar Arecibo Message, sent by Frank Drake in 1974. You’ll even hear how Frank worked himself into the message and what that has to do with Albrecht Durer’s self-portrait painted in the year 1500.

Finally, we turn to what Rebecca’s been up to recently. Her new book Mixed Signals came out in January of this year. Keep up with her on her website at and follow her on X @rebecca_charbon and on BlueSky @rebeccacharbon.bsky.social.

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

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What’s the difference between a maser and a megamaser? How does uncertainty lead science to its newest discoveries? To find out, Dr. Charles Liu and co-host Allen Liu welcome back radio astronomer Dr. Jackie Villadsen, a professor at Bucknell University currently researching star/planet magnetic interaction in exoplanet systems.

As always, though, we start off with the day’s joyfully cool cosmic thing. In November 2024 a group of researchers announced that they’d found a series of megamasers around the supermassive black hole system NGC1068, and that for the first time ever, they’d measured the polarization of the water megamasers. Jackie, who studies a different kind of maser, explains what they are (“just a really, really big laser pointer in space that shoots out radio waves or microwaves”) and why they’re important.

Jackie studies masers around nearby stars, which are much smaller than megamasers that can be seen from other galaxies. Allen shares the fact that some megamasers can be around half a parsec (trillions of miles) across and bigger than our entire solar system.

Then it’s time for our first question for Jackie. It’s from Guadalupe, who says, “I recall reading or watching a video that stated there is liquid on Mars beneath an "ice cap" - is that right?” According to Dr. Villadsen, the question is right on the cutting edge of our understanding, with promising evidence emerging right now that suggests the answer might be yes, although more investigation is necessary before we can confirm it.

After our break, Jackie tells us about the research she’s doing using the Karl G. Jansky Very Large Array (VLA) while on her current sabbatical. You’ll hear about Karl Jansky’s breakthrough discovery of radio waves from space made nearly 100 years ago. Jackie brings us up to speed on the evolution of radio astronomy and why we’re able to get more data than ever out of the same telescopes.

Our next question comes from Bryant: “What do you think would have happened if the universe was created a bit earlier than usual? Would anything have changed?” It turns out, there’s more than one way to look at this speculative question, and Jackie and Chuck ponder the possibility of having miscalculated the age of the universe and the impact that an older universe would have on the rate of universal expansion, the perception of dark energy, and more.

Next up, Jackie tells us about the research she and her colleagues (including grad students!) have been involved with looking for star/planet magnetic interaction in nearby exoplanet systems. The search is inspired by the interaction in our solar system between the magnetic field of Jupiter and two of its closest moons, Io and Ganymede. While there are no confirmed examples yet, they already have one candidate out of the seven exoplanet systems they’ve studied.

Our next question comes from Samuel, who asks, “As an astrophysics professor, how is the work-life balance and overall lifestyle of a researcher? My dream is to become a mechanical engineer in the field of astrophysics.” Jackie explains how she approaches work, and what it took to reach the balanced state she’s in now compared to when she was a grad student.

We end the episode with another of Jackie’s book recommendations. Last time she was here she recommended the adult sci-fi romance, “The Ladies Guide to Celestial Mechanics” by Olivia Waite. This time, it’s another adult sci-fi romance with a bit of a mystery woven through it, “The Stars Too Fondly” by Emily Hamilton. The title is taken from a poem, “The Old Astronomer to His Pupil” by Sarah Williams, from which Jackie reads a snippet. She and Chuck also discuss one of their favorite poems, “The Learned Astronomer,” by Walt Whitman, found in his collection, “Leaves of Grass.”

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

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#theliuniverse #charlesliu #allenliu #sciencepodcast #astronomypodcast #jackievilladsen #maser #megamaser #vla #verylargearray #exoplanets #jupiter #magneticfield #magnetosphere #aurora #wateronmars #blackholes #adultscifi #romance #thestarstoofondly #emilyhamilton #theoldastronomertohispupil #sarahwilliams #thelearnedastronomer #waltwhitman #leavesofgrass

Have you ever wondered how data from the telescopes that peer into our universe ends up in the hands of the astronomers who interpret it? To find out, Dr. Charles Liu and co-host Allen Liu welcome Robert Sparks, currently from the NSF’s NOIRLab, but previously Fermi Lab and the Sloan Sky Survey.

The National Optical InfraRed Astronomy Research Lab is responsible for operating the National Science Foundation’s ground based, nighttime optical and near infrared astronomy for the United States. Robert describes their Community Science Data Center which ties all the data from all their telescopes together to make it available for astronomers around the world to use in their research.

As always, though, we start off with the day’s joyfully cool cosmic thing, a project coming out of NOIRLab called 88 Constellations. Robert, who spearheaded the project, explains how the final, incredibly detailed image combined classic constellations and new, modern additions and covered the entire sky. One of his favorite parts of the project? Learning about the constellations in the southern hemisphere that doesn’t get to see that often, like the Southern Cross. Chuck, Allen and Robert share some of their experiences stargazing down below, and yes, you know Chuck takes the opportunity to sing us a little Crosby, Stills and Nash! You’ll also hear which constellation is the smallest in the southern hemisphere, Crux (the Southern Cross) or Delphinus.

Then it’s on to audience questions. Our first comes from Amirah, who asks, “Blue stars are hotter than red stars, so does that mean blue light bulbs are hotter than red light bulbs? Why would something's color matter about how hot something is?” The short answer: yes (pre-LED, that is!) Robert’s long answer involves black body radiation, the electromagnetic spectrum, and red giant carbon stars.

Rob shares stories from a career that bridges astronomy and particle physics, including how he got his hands on some original scintillator material from particle detectors at Fermi Lab. (Check out The LIUniverse on Patreon for a scintillating deep dive into…well, scintillation!)

The next audience question, from Bryan, is particularly relevant to the discussion: How do astronomy and physics work together? In many, ways, as Robert and Chuck explain. Allen shares the story of the discovery of the element Helium, which was first discovered in the Sun by astronomers, hence its name.

You’ll also get to hear about Robert’s 38-year-long career in improv comedy – and get to watch him (and his cat) act out scenes prompted by Chuck.

Finally, we’ve got one last audience question from Jerry, who says, “I live really far away from the city and I don't have a telescope. What's the best way for me to do astronomy research?” Robert, who grew up in Iowa, tells Jerry about citizen science astronomy projects he can get involved like those at The Zooniverse. You’ll hear about how, while working at a program there known as the Galaxy Zoo, a Dutch schoolteacher named Hanny Van Arkel discovered a weird light echo from a quasar that is now known as “Hanny’s Voorwep” (Hanny’s Object).

If you’d like to find out more about NOIRLab, the National Optical InfraRed Astronomy Research Lab, check out their website.

To keep up with Robert Sparks, you can follow him @halfastro on Bluesky, Threads, Flikr, and Instagram.

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

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#TheLIUniverse #CharlesLiu #AllenLiu #SciencePodcast #AstronomyPodcast  #NOIRLab #NSF #FermiLab #SloanDigitalSkySurvey #88Constellations #GalaxyZoo #TheZooniverse #blackbodyradiation #electromagneticspectrum #redgiants #carbonstars #particlephysics #scintillatormaterial #particledetectors #scintillation #HannysVoorwep

What were the coolest science and sci-fi events in the LIUniverse in 2024, and what’s in store for us in 2025? To find out, Dr. Charles Liu and co-host Allen Liu welcome three members of our production team: Leslie Mullen, our Executive Producer making her first on air appearance, Jon Barnes, our Editor, and Stacey Severn, our Social Media/Patreon Community Director, both of whom are familiar to longtime fans.

But first, as always, we start with the day’s joyfully cool cosmic thing: the latest development in the dispute that astrophysicists call the “Hubble Tension.” Over the past 20 years, the two different methods of measuring the Hubble Constant, which is used to calculate the rate of universal expansion, have led to two different conclusions. Leslie points out that the universe isn’t confused, we are, leading to a conversation about why accurate measurements matter in helping us expand our limited understanding.

Then we begin our look back at the year in astronomy – or rather, our look up. Stacey takes us on a tour, from a Geminid meteor hitting the moon, to the spectacular aurora borealis visible in the Northeastern US, to Comet C/2023 A3 Tsuchinshan-ATLAS, to, of course, the Great North American Eclipse. The team share their viewing experiences while Chuck explains the impact of solar max on both the eclipse and the auroras.

Next, Jon Barnes is back to talk about “The Three-Body Problem” science fiction series on Netflix. He asks Chuck to explain what we really know about cosmic particles (aka cosmic rays), because, in the series, the aliens use sophons, a supercomputer combined with a photon, to communicate across long distances at or near the speed of light. You’ll also hear about the recent detection of a surprisingly large number of very high energy cosmic rays that are hitting us right now.

Our fan question comes from Pshemo on Patreon and concerns an experiment to measure the dynamics of a local system relative to spacetime by using light as a way of gauging the background nature of the universe. And if you think that sounds pretty geeky, it’s nothing compared to the conversation between Allen, Chuck and Leslie that ensues, encompassing Einstein, the Michelson–Morley experiment, gravitational waves, LIGO, Virgo, KAGRA, and LISA.

There’s plenty more in this episode, including a discussion of the recent wave of drone sightings, their similarity to the past UFO sightings, and the likelihood that they are all explained by less exotic causes than aliens. Moving on to the coolest “identified flying objects” of 2024, Leslie tells us about the Europa Clipper, which launched in October. It will reach orbit around Jupiter in 6 years in order to search for alien life in the subsurface oceans of its icy moon Europa. Chuck reminds us all that NASA’s Parker Solar Probe will make its closest approach to our Sun on Christmas Eve 2024.

Finally, it’s time for the team to share what they’re looking forward to in 2025. Jon is psyched for “Mickey 17,” a film by director Bong Joon-ho about a clone on a space colony. Allen is excited for Rocket Lab’s Venus Life Finder, the first private interplanetary space probe, which launches in January to search for organic compounds within Venus' atmosphere. Stacey is looking forward to Axiom Space’s fourth mission to the ISS in 2025, an international trip to conduct scientific experiments commanded again by Peggy Whitson. Leslie is most excited for the discovery nobody is expecting, whatever that may be.

And what is Chuck looking forward to most in 2025? The long-awaited start of scientific operations at the Vera Rubin Observatory, which will take a full picture of the sky every 30 seconds for ten years and deliver an unprecedented level of data for astronomers to feast upon!

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

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How far can following your passions take you in science? To find out, Dr. Charles Liu and co-host Allen Liu welcome the multi-faceted Leah Voytovich, a software development engineer for Project Kuiper who planned on going to med school but instead ended up working on space lasers for Amazon’s satellite internet constellation.

As always, though, we start off with the day’s joyfully cool cosmic thing: the use of deuterium levels in the search for exoplanets with advanced civilizations. That’s because signs of deuterium depletion can indicate that a planet has developed nuclear fission power. 

After that, Leah tells us a little about Amazon’s Project Kuiper. She explains the wide variety of challenges to keeping the satellites, which are in low earth orbit, in communication with the ground. The project she’s working on now is using infrared space lasers to communicate more securely within the satellite constellation. 

Chuck brings up the impact that these massive groups of satellites like Starlink are having on astronomy, from satellite streaks on dark sky surveys to image-destroying flares. Leah said there are people working on reducing Project Kuiper’s impacts across multiple areas of concern.

For our first question. Yasmin asks, “Will our satellites all be controlled by AI someday? If so, when? And is this a good idea?” 

Leah speculates that there may be some projects already using Machine Learning here on Earth, but that it will be further down the line before there’s AI actually present in satellites themselves. Leah doesn’t see a problem with the use of ML tools for science, as long as there are protections in place and that humans are still writing the software.

After our break, Leah tells us about what she does outside her work – literally – from climbing Mount St. Helens in winter using an ice ax and crampons, to skiing, to running marathons – 3 so far!

Then we’re back to AI, ML, and the differences between the two. Charles talks about how important AI has beome as a tool for astronomers and other scientists. Leah explains the “Chinese Room Argument” and why it’s a good analogy for machine learning, Allen shares the description of AI as a “stochastic parrot.” 

Our next question comes from Jonathan, who asks, “With so many problems facing the world like poverty, war and the climate crisis here on Earth, why should we spend money and resources on space exploration and astronomy?”

Leah talks about how Project Kuiper is intended to serve underserved communities by providing internet access to people who don’t already have it. That in turn increases global communication and connectivity and can then help address those other problems. And of course, to launch those satellites, we need rockets.

She also explains how valuable internet access is to communities– something she knows a little about. She and Martin Leet co-founded Maji, a nonprofit in Uganda that uses solar power to make clean water easily accessible for refugee communities. Leah, a former EMT, explains how Maji also provides first aide medical training and agricultural training to the communities. The story of how Maji came to be is remarkable – we’ll leave it to Leah to share that with you in the episode.

We end with Leah recounting what it was like to be in Mission Control for the launch of the first Project Kuiper satellites. She was the representative for her team in the Mission Control room, so she was the one who actually got to say “Go” for her service during the final pre-launch Go/No Go review. 

If you’d like to know more about Maji, you can check out the nonprofit’s website here.

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

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