Starts With A Bang podcast

Discover the mysteries of our Universe as the conversation dives into the surprising complexities of gravity on different cosmic scales. Explore the intriguing world of wide binary stars and how they challenge conventional dark matter theories. Critique the limitations of general relativity while searching for more comprehensive gravitational models. Hear about groundbreaking advances in stellar cataloging from missions like Gaia, and how these discoveries could reshape our understanding of dark matter and the cosmos.

One of the most swiftly forgotten revolutions in all of science is our understanding of the Solar System out beyond Neptune. Although Pluto was discovered nearly a full century ago, it wasn't until the early 1990s that we even discovered the next object beyond Neptune that wasn't also part of the Plutonian system. And yet, in the 30 short years that have passed since then, we've learned so much more about the structure of the Kuiper belt and beyond, but we also face tremendous challenges in the quest to learn more thanks to an unwelcome intruder: the rise of satellite megaconstellations. Although the original team of Mike Brown and Konstantin Batygin continue to advocate for a novel, massive, undiscovered world located at hundreds of times the Earth-Sun distance, they're largely alone, as other scientists have weighed in and see no evidence for this hypothetical world. Nevertheless, more science must be conducted to know for sure, and in the meantime, the rise of satellite megaconstellations such as Starlink now poses an existential threat to all sorts of endeavors, including planetary astronomy. Here to guide us through the current status of the hunt for Planet Nine, as well as the new obstacles that astronomers are contending with, I'm so pleased to welcome Prof. Sam Lawler to the show. Sam is a professor at the University of Regina in Saskatchewan, Canada, and is also known for her advocacy work in favor of dark and quiet skies for all of humanity to enjoy and benefit from. It's a fascinating discussion that took me to some unexpected places, and I think you'll enjoy it a whole lot! (This image shows an illustration of the hypothetical Planet Nine: a planet theorized to be more massive than Earth but hundreds of times farther away from the Sun than our own world. Credit: Tobias Roetsch/Future Publishing)

Every January, I head to the American Astronomical Society's big annual meeting with an ulterior motive in mind. Beyond merely uncovering new scientific findings, gathering information for potential stories, and connecting with friends and colleagues, I also look to meet emerging junior researchers who are swiftly becoming not only experts, but leaders, in their particular sub-field of astronomy. One of the most popular research topics in astrophysics today is the connection between the dark Universe, including the only indirectly-observed dark matter and dark energy, and the observable components that astronomers routinely see: stars, galaxies, gas, plasma, and other forms of light-emitting and light-absorbing matter. The dark Universe, to date, is best revealed by looking at the luminous, electromagnetic signals that are imprinted onto the visible components of our cosmos. To better understand what scientists are investigating, I'm so pleased to welcome KeShawn Ivory to the podcast. KeShawn is a PhD candidate at Vanderbilt University and researches the connection between dark matter, the non-luminous, gravitationally interacting "stuff" that holds the Universe together (as best as it can), and the luminous, observable galaxies that populate the visible Universe in numbers that rise into the trillions. It's a fascinating topic and a great addition to your May listening, right here on Starts With A Bang! (The SIBELIUS project, which simulates galaxies and structures beyond the local Universe, is part of the Virgo Consortium that attempts to use cosmological simulations to reproduce features of galaxies, groups, and clusters that are seen all across the Universe. By using a mix of theory, observations, and simulations, astrophysicists can better understand the nature of dark matter in our cosmos. Credit: Virgo Consortium/SIBELIUS project)

Discover the secrets of the magnetized galactic center through multiwavelength astronomy. Dr. Natalie Butterfield discusses her groundbreaking discovery of a giant magnetized ring and the FIREPLACE survey. Explore the challenges of observing the galactic center and the importance of radio emissions in studying magnetic fields. Learn about the composition of interstellar clouds, spectroscopy in astronomy, and the future of exploring the universe with next-generation telescopes.

Explore the variety of galaxies in the Universe and the presence of supermassive black holes at their centers. Learn about phenomena like accretion disks, jets, and emitted radiation in active galaxies. Discover the impact of active galaxies on the larger structures in the Universe. Join Skylar Grayson in unraveling the role of these galaxies in shaping the cosmos.

Up until the early 1990s, we didn't know what sorts of planets lived around stars other than our Sun. Were they like our own Solar System, with inner, rocky planets close to our star and large, giant worlds farther away? It turned out that exoplanetary systems come in a great variety of configurations: with planets of all sizes, masses, and distances from their parent stars. But some configurations are more common than others. There are lots of hot Earth-sized planets and lots of hot Jupiter-sized planets, but precious few "hot Neptune" worlds out there. Furthermore, there appear to be lots of Earth-sized and super-Earth-sized worlds at greater distances, as well as many Neptune-sized and mini-Neptune-sized worlds. However, there's a gap there, too: between the large super-Earths and the small mini-Neptunes. Where are these missing exoplanets? Or, rather, why are these classes of exoplanets so uncommon? That's what we're exploring on this episode of the Starts With a Bang podcast, featuring Ph.D. candidate Dakotah Tyler as our guest this month. By looking at how a hot (but low-mass) Jupiter-sized planet is being photoevaporated by its parent star, we can learn so much about not only the classes of objects we see out there, but even the ones we don't! (Around the star WASP-69, a "hot Jupiter" exoplanet has its outer layers of atmosphere photoevaporated away, creating a comet-like tail whose extent and mass were recently measured for the first time. Credit: W. M. Keck Observatory/Adam Makarenko)

Happy new year, everyone, and with a new year comes a spectacular new podcast! We normally cover an intricate and underappreciated aspect of astrophysics on the podcast, but I had the opportunity to bring on a true expert in the field of quantum computing and just couldn't pass it up. You've likely heard a lot of noise about quantum computers and the benefits that they're poised to bring, with buzzwords like "P=NP," "quantum supremacy," and "quantum advantage" tossed around, but a lot of what you're likely to hear is hype, not actual science. Good thing I was able to get Dr. Riccardo Manenti as a guest for our podcast! Riccardo is the author of a state-of-the-art textbook on quantum computers, has his PhD from Oxford in Quantum Computing, and has been working for Quantum Computing startup Rigetti for several years now. Join us as he helps demystify some of the recent progress and problems right here on the cutting edge of this promising new arena of physics, right here on the Starts With A Bang podcast! (This illustration show's Rigetti's widely-available quantum computer, Novera, with 9 superconducting physical cubits within it. The great hope is that by scaling up to greater numbers of physical qubits, quantum advantage will be an achievable milestone in the relatively near future. Credit: Rigetti/Novera)

Learn about the profound discoveries made by JWST, including the farthest black hole, most distant galaxy, and farthest red supergiant star. Dr. Jeyhan Kartaltepe shares insights on the cutting edge of these discoveries and how they challenge our understanding of the Universe. Explore the advantages of JWST over the Hubble telescope and its capabilities in observing diverse early galaxies. Discover the importance of spectroscopy in identifying distant galaxies and the future discoveries expected with JWST.

You might not think about it very often, but when it comes to the question of "how old is a star that we're observing," there are some very simple approximations that we make: measure its mass, radius, temperature, and luminosity (and maybe metallicity, too, for an extra layer of accuracy), and we'll tell you the age of this star, including how far along it is and how long we have to go until it meets its demise. This also operates under a simple but not-always-accurate assumption: that all stars of a given mass and composition have the same age-radius and radius-temperature-luminosity relationships. That simply isn't true! Stars vary, both over time as they evolve and also from star-to-star dependent on their rotation and magnetism. It's a funny situation, because just a few years ago, people had declared stellar evolution as a basically "solved" field, and now it turns out that we might have to rethink how we've been thinking about the most common classes of stars of all! To help us explore this topic, I'm so pleased to welcome Dr. Lyra Cao (pronounced "Tsao" and not "Cow" in case you were interested) to the program, where she helps walk us through what we're only now learning about stars: particularly young stars, low-mass stars, and rapidly rotating stars. If you know nothing about stellar evolution, this will be a treat for you, as you won't have to un-learn a massive amount of information to make sense of the Universe! (This image shows a temperature profile of star HD 12545, which unlike our Sun, doesn't just have a small number of tiny sunspots on it, but is dominated by a massive, star-spanning starspot that covers approximately 25% of its surface. Many stars, including low-mass, young, and rapidly rotating stars, have enormous sunspots that can play a major role in the habitability of their systems. Credit: K.Strassmeier, Vienna, NOIRLab/NSF/AURA)

Out there in the Universe, there's a whole lot more than simply what we find in our own Solar System. Here at home, the largest, most massive object is the Sun: a bright, hot, luminous star, while the second most massive object is Jupiter: a mere gas giant planet, exhibiting a small amount of self-compression due to the force of gravity. But elsewhere in the Milky Way and beyond, numerous classes of objects exist in that murky "in-between" space. There are stars less luminous and lower in mass: the K-type stars as well as the most numerous star of all: the red dwarf. At even lower masses, there are brown dwarf stars, possessing various temperatures ranging from a little over ~1000 K all the way down to just ~250 K at the ultra-cool end. These "in-between" objects, not massive enough to be a star but too massive to be a planet, have their own atmospheres, weather, and a variety of other properties. The thing that limits our knowledge of them, at present, is merely our own instruments. That's why, on this edition of the Starts With A Bang podcast, I'm so pleased to welcome Dr. Brittany Miles, an expert on ultra-cool brown dwarfs and a specialist in instrumentation technology. If you were ever curious about these "in between" objects, you won't want to miss this journey to the frontiers of modern astronomical science! (This graphic compares a Sun-like star with a red dwarf, a typical brown dwarf, an ultra-cool brown dwarf, and a planet like Jupiter. While brown dwarfs are neither star nor planet, they're fascinating objects in their own right, and very much part of the cosmic story uniting us all. Credit: MPIA/V. Joergens)