Starts With A Bang Podcast

Earlier this year, 2019, the Event Horizon Telescope collaboration revealed the first image that directly showed the existence of an event horizon around a black hole. This image, constructed from many petabytes of data from telescopes observing the same target, simultaneously, from all across the Earth, provided a breathtaking confirmation of Einstein's relativity in a realm where it had never been tested before. But that's just one image of one black hole at one particular moment in time, and there's so much more to come from the Event Horizon Telescope. This month, we're so fortunate to sit down with EHT scientist Sara Issaoun, who takes us through the past, present, and future hopes for the Event Horizon Telescope and how it hopes to answer humanity's biggest questions about black holes. (Image credit: APEX, IRAM, G. Narayanan, J. McMahon, JCMT/JAC, S. Hostler, D. Harvey, ESO/C. Malin)

What do we really know, and what mysteries are left to solve, about the outer worlds of our Solar System, and about the gas giant and ice giant worlds found throughout the Universe? Remarkably, if you had asked this same question 30 years ago, we would have had a quaint story about how planets form and why our Solar System has the planets it does, and we assumed that these rules would be extended to all solar systems in the galaxy and Universe. But with the deluge of exoplanet data, accompanied by better observations and simulations of our Solar System, that old story isn't even the half of it. I'm so lucky to get to interview Heidi Hammel for this edition of the podcast, who, as a bonus, was the lead investigator on the Hubble Space telescope when Comet Shoemaker-Levy 9 impacted Jupiter back in 1994! Come listen to one of my favorite interviews ever today! (Image credit: NASA/Voyager 2)

We know that there's more to the Universe than we presently know. As successful as the Standard Model may be, it cannot describe everything we observe to be true about the Universe. Neutrinos oscillate from one flavor into another, and must have a non-zero mass, but we don't understand why or how. Dark matter has an overwhelming suite of astrophysical evidence that points towards its existence, but we have no direct evidence for the type of particle it might be. What do we do about these puzzles? We perform the best experiments we can to try and probe, identify, and constrain the novel physics that might be responsible for these unexplained phenomena. This month, I'm so pleased to chat with Doctor Laura Manenti, postdoctoral research associate at NYU Abu Dhabi and a researcher on the XENON1T and the Proto-DUNE experiments. Take a dive into the world of experimental particle physics on the latest Starts With A Bang podcast! (Image credit: Enrico Sacchetti.)

With all the planets out there in the galaxy and Universe, it's only a matter of time and data until we find another one with life on it. (Probably.) But while most of the searches have focused on finding the next Earth, sometimes called Earth 2.0, that's very likely an overly restrictive way to look for life. Biosignatures, or more conservatively, bio-hints, might not only be plentiful on worlds very different from our own, but around Solar Systems other than our own. Earth-like worlds, in fact, might not even be the most ubiquitous places for life to arise in the Universe. I'm happy to welcome scientist Adrian Lenardic onto the Starts With A Bang podcast, and explore what just might be out there if we look for life beyond our idea of Earth 2.0! (Image credit: JPL-Caltech/NASA.)

One of the biggest conundrums in the Universe surrounds the question of how quickly the Universe is expanding. Questions like what is the Universe made of, how old is it, what is it's ultimate fate, etc., absolutely depend on this. For generations, we argued over the details of this, seeming to have finally reached a consensus in 2001 with the Hubble Key Project's results: 72 km/s/Mpc, with an uncertainty of about 10%. But the modern results, as of 2019, seem to depend on how you measure it. Some teams are consistently getting 67 km/s/Mpc, while others get 73-74 km/s/Mpc, with uncertainties that don't overlap. This may not be a controversy, but rather a clue, and Nobel Prizewinner and co-discoverer of dark energy Adam Riess joins me on this special edition of the Starts With A Bang podcast. Don't miss it! (Image credit: NASA / GSFC)

When we think about finding planets in the Universe, we typically look for ways to detect them as they orbit their parents stars, either affecting their star's position or velocity, or blocking or reflecting a certain portion of their light. But what about the planets that are too small to be detected that way? What about the planets whose effects are imperceptible? And what about the rogue planets: the ones that no longer (or perhaps never did) orbit a star of their own? Well, they're not doomed to be invisible! In fact, we can measure and characterize them extremely well, through the power of gravitational microlensing. This isn't some pipe dream of science fiction that may someday come to fruition; it's real, current science that expects a tremendous explosion of planetary discoveries with WFIRST's launch in the mid-2020s. Come find out what the future of this fascinating scientific field holds as we launch into a tremendous conversation with researcher Savannah Jacklin, as we explore the microlensing Un

So, you want to know about black holes, including how we're seeing them, what happens when you fall into them, what our future plans for direct and indirect detection are, and how scientists are answering some of the biggest questions about them today? It's a fascinating story about some of the most mind-blowing objects in the Universe. Please welcome Assistant Professor of Astronomy and Physics at the University of Mississippi, Dr. Leo C. Stein, to the show, and enjoy a 1 hour+ conversation where we explore some of the deepest concepts in cutting-edge physics and gravitational wave astronomy! (Image credit: Northwestern Visualization/Carl Rodriguez)

After the Big Bang, it took only a few hundred thousand years for the Universe to form neutral atoms. But it took tens or even hundreds of millions of years for the first stars to turn on, and a whopping 550 million years for those neutral atoms to all become reionized by that starlight once again. Believe it or not, we can measure not only the starlight coming from the stars that do form through the now-infrared light they emit, but also the neutral atoms themselves through the power of 21-cm astronomy. I'm joined this week by Dr. Elizabeth Fernandez, research astronomer, science communicator and podcaster extraordinaire on her show, SparkDialog. (Check it out, here: http://sparkdialog.com/) How did the Universe grow up to be the way it is today? Take another spectacular step on the latest edition of the Starts With A Bang podcast.

One of the great goals in our study of the Universe is to see past the currently-known frontiers. That means going farther, to greater and greater distances. It means going fainter, to smaller and less-easy-to-see objects. It means going to earlier times and less-evolved conditions. And it means detecting more of the Universe than we've ever seen before. Our goal is the most ambitious one you can imagine: understanding what the Universe was like when it was born, how it grew to be the way it is today, and where it's headed in the future. One huge step that we only took this decade was to detect the first pristine matter left over from the Big Bang, before any stars or galaxies formed from it. A second, that we're taking today, is to try and create a better space-based observatory than Hubble or even James Webb. On this edition of the Starts With A Bang podcast, we talk about both of these issues with astronomer and chief scientist at the Keck Observatory: John O'Meara. Enjoy!

Is there intelligent life out there in the Universe beyond planet Earth? If so, are they technologically advances, can they hear us, and are they broadcasting in ways that we could possibly detect them? In the absence of their arrival on Earth, you might think that there's no surefire way to know. But the scientists working hard on SETI, the Search for ExtraTerrestrial Intelligence, sure are trying their best. By listening to the Universe at large (and our galaxy in particular), they're hoping to uncover the answer to perhaps the ultimate question: whether there's a civilization out there that humanity might hope to make contact with, and that could perhaps be our ally in uncovering the great mysteries of the Universe. I'm so pleased to welcome astronomer and senior scientist at the SETI Institute, Seth Shostak, onto this edition of the Starts With A Bang Podcast!

In 2017, the incredible happened: for the first time in history, we were able to identify an object passing through our Solar System that originated from outside of it! Interstellar interloper 'Oumuamua was originally designated as a comet, then as an asteroid, and then as a new class of object: one of interstellar origin. It's a fascinating object that's the first of its kind, and much has been said about its composition, properties, and possible nature. But, unfortunately, the most famous of those "nature" discussions was from Schmuel Baily and Avi Loeb of Harvard, claiming that it could be due to aliens. Is that plausible? Is that even science? My guest for this edition is astrophysicist Paul Matt Sutter, author of the new book Your Place In The Universe, and we have an almost-hour-long discussion that goes to some fantastic and unexpected places. You won't want to miss it! Find Paul online on Twitter https://twitter.com/PaulMattSutter, Video: http://www.pmsutter.com/shows/askaspaceman/, Book: Your Place

Our Solar System formed some 4.6 billion years ago from a molecular cloud that collapsed. Our proto-Sun formed along with a protoplanetary disk that eventually evolved into the Solar System we have today, complete with the inner, rocky planets, an asteroid belt, the gas giants and their moons and ringed systems, and then the outer Solar System. Those outer regions sure are interesting, and it's only over the past 3 decades we've really started to learn about them in earnest. I had the opportunity to speak with outer Solar System specialist Michele Bannister, and she agreed to be this month's guest on our podcast. Oh, did an exciting discussion ensure, and we've got over an hour of knowledge for you! What's the status on how the Solar System formed, on Planet Nine and its alternatives, and what the prospects are for taking the next major steps? Find out on this edition of the Starts With A Bang podcast! Find Michele here at her current research location: https://pure.qub.ac.uk/portal/en/persons/michele-bann

I'm so pleased to welcome Dr. Erin MacDonald to the Starts With A Bang podcast, as we discuss the future of Gravitational Wave astronomy. From pulsars to merging black holes, to kilonovae to hopes of observing gravitational wave signatures from the earliest moments of the Universe, we cover a whole lot of astrophysics, cosmology, and experimental hopes for the near future in this burgeoning new field of astronomy. The future of gravitational wave science is so bright, even without the collection of any light. Come learn all about it today! Find Dr. Erin MacDonald online here: Website: www.erinpmacdonald.com YouTube: www.youtube.com/c/erinmacdonald

There's been a lot of speculative ideas put forth about the Multiverse, and I dare say that a great many of them are nothing more than wishful thinking. But that doesn't mean the Multiverse itself is ill-motivated at all. Rather, if you take two of our best theories that have been well-confirmed in a wide variety of different ways, you're going to find that you arrive at a bizarre but unavoidable picture: one of an inflating spacetime, eternal to the future, where regions that look like our Universe, complete with a hot Big Bang, are spawned continuously. The evidence might not be there, observably, to confirm or deny the existence of a Multiverse. But as a theoretical consequence, it certainly has a motivation that's far stronger than practically anyone realizes. Here's the cosmic story.

The Universe, today, is expanding and cooling, as the volume of the Universe increases while the number of particles within it remains constant. If you extrapolate forwards in time, the Universe gets sparser, less dense, and closer to being completely empty. But if you extrapolate back in time instead, the Universe gets hotter, denser, and smaller in volume. Eventually, if you didn't stop yourself, you'd go all the way back to a state of infinite density, where all the matter was packed into a single point: a singularity. This was where, when it was first formulated, the idea of a Big Bang singularity came from, and the idea that space and time had a beginning. Yet we no longer believe that to be true! Why not? Come find out on this edition of the Starts With A Bang podcast!

Have you ever wondered what's out there in the Universe, on the largest scales, beyond what we can even observe? Or what lies down below the tiniest distance scales we've ever probed? Is there a smallest fundamental length scale in the Universe, like the Planck scale, or can we go down even farther? Is space discrete or continuous? And is the Universe fundamentally blurred; can we even distinguish? Thinking about the limits of space, on both small and large scales, is a mind-bending game to play, but we're up to the challenge on this latest edition of the Starts With A Bang podcast!

There are three very different ways humanity is searching for alien life beyond Earth. We can directly search the various planets and moons in our Solar System for past or present biological signatures simply by sending decontaminated probes, and looking for the evidence in situ. We can indirectly look at distant worlds around other stars, searching for the characteristic changes to the atmosphere and surface that life would bring. And, most optimistically, we can search for intelligent signatures created, perhaps willfully, by a technologically advanced alien species. These are our three hopes for finding alien life, and we're actively pursuing all three. Here's how the different searches work, along with some speculation about what we're likely to find, and what motivates us to look!

There are some incredibly big questions that humanity has been asking about the Universe since we first began looking upwards: what is the Universe like, how did it get to be this way, where did it all come from, and what is its eventual fate? There were huge advances that were needed in order to answer these questions, such as understanding what the Universe was made of, how fast it was expanding, and what the laws governing it were. But once we know that, not only can we answer these questions, but we can do it with a single equation. It's known as the First Friedmann equation, and I call it the most important equation in the Universe. Find out why on this edition of the Starts With A Bang podcast!

In memory of Stephen Hawking's life, I've decided to share the physics behind his greatest discovery: Hawking radiation. For a long time, in the context of relativity, we thought that black holes were static, unchanging objects defined only by their mass, charge, and angular momentum. A number of developments led us to understand that black holes needed to have entropy, temperature, and therefore, they needed to radiate. But Hawking was the one to put that puzzle together, and describe the physics of the radiation and its consequences for black holes. It goes much further than that, with the famed (and still unresolved) black hole information paradox arising from his work. Who will be the ones who take the next great leap? Come learn what we know and where the frontiers are on this special edition of the Starts With A Bang podcast!

When you fall inside the event horizon of a black hole, there's no escaping, no matter what you do or how you accelerate. Even if you travel at the Universe's speed limit, the speed of light, there's simply no way to get any closer to the exit. Instead, scientists say, you have no choice but to fall inevitably towards the singularity at the center. But why must you arrive at a singularity? Couldn't you wind up at some degenerate object instead? We don't think so, and here's the science behind why. Find out what's at the center of a black hole today!