Starts With A Bang Podcast

In 1930, Clyde Tombaugh discovered Pluto: our Solar System's ninth planet. For over 60 years, the Plutonian system was the only one known beyond Neptune, and Pluto retained its planetary status for all that time despite its diminutive size. Yet an explosion of exoplanets and of other Trans-Neptunian Objects within our own Solar System beginning in the 1990s meant that we'd need to reconsider what it means to truly be a "planet". The debate still rages today, but astronomers agree: when it comes to the planetary club, Pluto simply doesn't belong. Here's why!

Our Universe was born pristine, with no stars, galaxies, molecules or even stable atoms, some 13.8 billion years ago. Yet today, we're filled with all the complex structure we see today, including with planets, organics and even something as complex and differentiated as a human being. So how did we get here? We had to form stars and galaxies, and evolve the Universe to a point where the raw ingredients to make us existed in great enough abundances and in the right conditions. There are some steps we're still learning about in this story, including how the very first stars came to be. Want to learn about it? Find out on this latest Starts With A Bang podcast!

The discovery almost 100 years ago that the Universe was expanding was a revolution for science, for cosmology and for our conception of existence. Hubble discovered what Einstein's couldn't imagine, and after that, the race was on to learn exactly what those observations meant for our cosmic origins. After decades of controversies, we now have a better picture of our Universe than ever before, yet questions remain. What will be the ultimate answer? Find out the possibilities, and what the limits of our knowledge tell us is possible, on this edition of the Starts With A Bang podcast!

Black holes are incredibly massive objects that are so dense that, from within a given region of space, nothing can escape, not even light. Yet it's arguable that from our point of view, nothing can escape our observable Universe. Moreover, even though our Universe is huge, it's also incredibly massive, and since it's expanding, it was denser and smaller in the past. Could our Universe be the inside of a black hole? And do we have evidence either supporting this or ruling it out? Find out on the latest episode of the Starts With A Bang podcast!

Ever since we first uncovered the quantum nature of our Universe, humanity has struggled to interpret it. Is there a wavefunction that collapses? Is it the quantum operators themselves that change? Does the end state evolve? Or are there an infinite number of parallel Universes that correspond to all the possible outcomes? This last possibility may actually be plausible, and this podcast is a deep dive into the adventure that ensues if they're real. But beware, there are a lot of assumptions needed to get there!

Did you hear the news, that it isn't "billions and billions" anymore, but that there are TWO TRILLION (or 2,000,000,000,000) galaxies in the observable Universe? Come get the science behind this amazing story, including how we know, what it means and what we'll even have the potential to learn in the near future.

For thousands upon thousands of years, we didn't know whether the other stars in the Universe were even like our Sun, much less whether they had planets around them like we find in our Solar System. Over the past 25 years, however, that question has not only been answered, but we've discovered thousands of confirmed planets. Even more exciting, we've found that the star systems out there are similar to our own in some ways but tremendously different in others, and that there are already more than 20 rocky planets known that are at the right distance to have liquid water on their surface, given Earth-like atmospheres. This includes the closest star to our own: Proxima Centauri, whose planet 'Proxima b' just might be our first step into the Universe beyond our Solar System. Enjoy!

Our Universe has been expanding and evolving since the hot, dense, expanding state known as the Big Bang first came to be. But there was a "day without yesterday," where the Big Bang occurred at a moment in time! Was that the birth of space and time itself? Or was there a pre-existing state that came before and gave rise to the Big Bang? Come find out the evidence that's led us to our greatest conclusions about the very beginning of where everything came from!

While there are presently more than ~10^23 stars in the Universe shining today, each one of them is fated to live only for a finite amount of time. While more and more will continue to form, we're already past the point of peak star formation in the Universe. How long will we have until, for the last time, the Universe's last star goes out? Find out on this edition of the Starts With A Bang podcast!

Ever since humanity had the thought that the distant, twinkling stars might be Suns like our own, with their own planetary systems and chances at life, we've dreamed of extending humanity's reach to the galaxy and beyond. What are our actual chances of doing so, technologically, scientifically and practically? This podcast -- based on an exclusive interview with Larry Niven -- explores what's possible.

How will the Universe end? Will it recollapse in on itself, ending in a Big Crunch? Will it expand forever, ending in a Big Freeze? Or will it tear itself apart, ending in a Big Rip? With the discovery of dark energy, we finally think we know, but there's always more science to be done, more possibilities to consider, and new evidence to look for to help point the way.

Could there be a ninth planet in our Solar System, farther out than Neptune? Recent evidence points to a tantalizing possibliity, and searches are underway to look for it. Here's the science behind the full 'Planet Nine' story, in one amazing, easy-to-follow podcast!

The Hubble Space Telescope has just shattered the record for most distant galaxy in the Universe. How did we break this record, and what do we expect to find even farther back?

In February of 2016, less than six months after first becoming operational, LIGO (the laser interferometer gravitational wave observatory) announced the first-ever direct detection of gravitational waves. What are they? What does it mean? What did we learn? And what can we do with them now that we know they exist? All this and more on this month's Starts With A Bang podcast!

In 1930, Clyde Tombaugh serendipitously discovered Pluto: the first object in our Solar System out past Neptune. For 48 years, it was the only object known out there, until Charon -- its giant moon -- was discovered. But the 1990s brought with it a slew of Kuiper Belt objects, and in 2006, Pluto was officially demoted to a "dwarf planet." But also in 2006, NASA's New Horizons mission was launched: the first dedicated mission to the outer Solar System. In 2015, it flew by both Pluto and Charon, discovering two vastly different worlds. Here's what we've learned.

Everywhere we look in the Universe, we find that planets, stars, galaxies, and even the gas between them are all made of matter and not antimatter. Yet as far as we know, the laws of nature are symmetric between matter and antimatter: you can't create or destroy one without the other. So how did our Universe get to be the way it is? Come right up to the frontiers of our scientific knowledge and have a listen!

Although it's been only 13.8 billion years since the Big Bang, we can see objects as distant as 46.1 billion light years away. How is this possible? Ethan Siegel explains in the second Starts With A Bang podcast. Plus, how to see Comet Catalina in the December skies, and why it's on its way out of the Solar System forever. This podcast is free to download and distribute in perpetuity thanks to the support of our Patreon donors at www.patreon.com/startswithabang?ty=h

In the first inaugural Starts With A Bang podcast, astrophysicist Ethan Siegel discusses the latest evidence for water on Mars, what it means for Earth and potential life on the surface, as well as other topics. Guest (and Patreon supporter) Maciek makes an appearance, and we discuss the future of physics and speculate on what the next great advance might be. This podcast is free to download and distribute in perpetuity thanks to the support of our Patreon donors at https://www.patreon.com/startswithabang?ty=h