I’m not saying it’s aliens, but it’s aliens. Actually, it’s almost certainly not aliens, or a wormhole, or a multiverse. When scientists discover something unusual, they make guesses about what’s happening. But Occam’s Razor encourages us to consider the probabilities of different events before making any concrete predictions.
Ep. 389: Roundtable with Paul Sutter
While Pamela and Fraser were at Ohio State University for a symposium in October, they caught up with Paul M. Sutter from Astronomical Observatory of Trieste, who is a visiting scholar at the OSU Center for Cosmology and Astro-Particle Physics. His specialty is cosmic voids. Paul also hosts the “Ask a Spaceman” podcast.
Ep 388: Megastructures
This week astronomers announced an unusual transit signal from another star. Although it’s most likely a natural phenomenon, one remote possibility is that this is some kind of alien mega-structure. Freeman Dyson and others have considered this idea for decades. Today we’ll talk about the kinds of structures that aliens might want to build.
Ep 387: Water on Mars… Again
Have you heard the big news? NASA has reported that Mark Watney is alive and well on the surface of Mars. No, wait, they’ve reported that there’s water on Mars. Didn’t they already report this? Today we’ll update you on the latest discovery and what this means for the search for life on Mars.
Ep 386: Orbiting Observers
The atmosphere keeps us alive and breathing, but it really sucks for astronomy. Fortunately, humanity has built and launched space telescopes that get above the pesky atmosphere, where the skies are really clear. Let’s take a look at the past, current and future of orbital observation.
Ep 385: Rovers on the Run
Taking pictures of distant worlds is great and all, but the best science happens with boots on the ground. Or in this case… wheels. This week we’ll talk all about robotic rovers and the places they rove.
Ep. 384: Escaping Probes
The gravity of the Earth is a tough thing to escape, but breaking free from the gravity of the Sun is on a whole other level. But humans have achieved this amazing accomplishment, and right now there are several spacecraft leaving the Solar System and never coming back.
Ep. 381: Hollowing Asteroids in Science and Fiction
When we finally make the jump to fully colonizing the Solar System, we’re going to want to use asteroids as stepping stones. We can use them as way stations, research facilities, even as spacecraft to further explore the Solar System. Today we’ll talk about the science and science fiction of hollowing out asteroids.
Ep. 380: The Limits of Optics
Astronomers rely on the optics of their instruments, and there are some basic limits that you just can’t avoid. Whatever we look at is distorted by the optics, in fact, a basic property of light means that we’ll never get perfect optics. Here’s why we can’t “magnify and enhance” forever.
Ep. 375: The Search For Life in the Solar System
With the discovery of water ice in so many locations in the Solar System, scientists are hopeful in the search for life on other worlds. Guest Morgan Rehnberg returns to Astronomy Cast to explain the best places we should be looking for life.
Ep. 374: Stern-Gerlach Experiment
In the world of quantum mechanics, particles behave in discreet ways. One breakthrough experiment was the Stern-Gerlach Experiment, performed in 1922. They passed silver atoms through a magnetic field and watched how the spin of the atoms caused the particles to deflect in a very specific way.
Ep. 369: The Fizeau Experiment
Light is tricky stuff, and it took scientists hundreds of years to puzzle out what this stuff is. But they poked and prodded at it with many clever experiments to try to measure its speed, motion and interaction with the rest of the Universe. For example, the Fizeau Experiment, which ran light through moving water to see if that caused a difference.
Ep. 367: Spitzer does Exoplanets
We’ve spent the last few weeks talking about different ways astronomers are searching for exoplanets. But now we reach the most exciting part of this story: actually imaging these planets directly. Today we’re going to talk about the work NASA’s Spitzer Space Telescope has done viewing the atmospheres of distant planets.
Ep. 366: HARPS Spectrograph
Almost all the planet hunting has been done from space. But there’s a new instrument installed on the European Southern Observatory’s 3.6 meter telescope called the High Accuracy Radial velocity Planet Searcher which has already turned up 130 planets. Is this the future? Searching for planets from the ground?
Ep. 365: Gaia
The European Gaia spacecraft launched about a year ago with the ambitious goal of mapping one billion years in the Milky Way. That’s 1% of all the stars in our entire galaxy, which it will monitor about 70 times over its 5-year mission. If all goes well, we’ll learn an enormous amount about the structure, movements and evolution of the stars in our galaxy. It’ll even find half a million quasars.
Ep. 364: The COROT Mission
Before NASA’s Kepler mission searched for exoplanets using the transit method, there was the European COROT mission, launched in 2006. It was sent to search for planets with short orbital periods and find solar oscillations in stars. It was an incredibly productive mission, and the focus of today’s show.
Ep. 363: Where Did Earth's Water Come From?
Where on Earth did our water come from. Well, obviously not from Earth, of course, but from space. But did it come from comets, or did the water form naturally right here in the Solar System, and the Earth just scooped it up?
Ep. 362: Modern Women: Carolyn Porco
It hard to think of a more influential modern planetary scientist than Carolyn Porco, the leader of the imaging team for NASA’s Cassini mission exploring Saturn. But before Cassini, Porco was involved in Voyager missions, and she’ll be leading up the imaging team for New Horizons.
Ep. 361: Modern Women: Maria Zuber
Maria Zuber is one of the hardest working scientists in planetary science, being a part of six different space missions to explore the Solar System. Currently, she’s the lead investigator for NASA’s GRAIL mission.
Ep. 360: Modern Women: Jocelyn Bell Burnell
Jocelyn Bell Burnell is an Irish astronomer, best known for being part of the team that discovered pulsars, and the following controversy when she was excluded from the Nobel Prize winning team.
Ep. 359: Modern Women: Margaret Geller
Margaret Geller is best known for her work on the large scale structure of the Universe, helping us understand the large clusters, super clusters and cosmic filaments that matter clumps into.
Ep. 358: Modern Women: Sandra Faber
Our focus on female astronomers continues with Sandra Faber, and Professor of Astronomy at UC Santa Cruz. Faber was part of the team that turned up the Great Attractor, a mysterious mass hidden by the disk of the Milky Way.
Ep. 355: Maker Space: 3D Printing Exploration
Getting stuff into space is complicated and expensive. And what do you do when your fancy space gadget breaks. You print out a new one, of course, with your fancy space 3D printer. It turns out, space exploration is one of the best uses for this technology.
Ep. 354: Comet Siding Spring vs. Mars
We were witness to a once in a million year event. A close approach of Comet Siding Spring to the Planet Mars. And fortunately, humanity had a fleet of spacecraft orbiting the Red Planet, ready to capture this monumental event in real time. What did we see? What will we learn?
Ep. 353: Seasons on Saturn
You think we’re the only place that experiences seasons? Well, think again. Anything with a tilt enjoys the changing seasons, and that includes one of the most dramatic places in the Solar System: Saturn, with its rings and collection of moons.