What color is the Universe? Turns out this isn’t a simple question, and one that scientists have really been unable to answer, until now!
Ep. 411: Science of Sunset Colors
We all enjoy beautiful, multicolored sunsets. But what causes the brilliant oranges, pinks and purples that we see, and why does it change from day to day and season to season?
Ep. 410: Planet 9 Facts and Fiction
The discovery of Planet 9 has caused a wonderful, confusing uproar and a flood of misinformation in the news and social media. We’ll sort out what we actually know, what things just aren’t true, and what things might be possible!
Ep. 409: Spin in the Solar System
The Solar System is a spinny place. Everything’s turning turning. But if you look closely, there are some pretty strange spins going on. Today we talk about how everything started turning, and the factors that still “impact” them today.
Ep. 405: Method Not Found
Last week we talked about knowledge, what we do and don’t know. This week we talk about questions which are impossible to ask, where the answers don’t actually exist.
Ep. 404: The Difference Between: Can’t Know, Don’t Know, & Just Awaiting Better Tech
There the things we know, the things we don’t know, and the things we can’t know. How do we know which one is when when we’re deciding to fund research and direct our scientific inquiry.
Ep. 403: Funding Big Science: from Alma to LIGO to TMT
How much of a challenge is it to get funding for large projects like LIGO? Fraser and Pamela discuss the difficult issues finding “Big Money.”
Ep. 402: Gravity Eyes: See The Invisible With The Force
What kinds of things can we see using gravity, that we may not otherwise be able to see? Pamela will fill us in on the Great Attractor, etc!
Ep. 401: Future Predictions
What do Pamela and Fraser think will happen or be discovered in 2016? What would they like to see in the near future?
Ep. 400: The State of the Universe
It’s time for us to go back and catch up with all of the projects, news stories, weird star systems, and other topics that need updating!
Ep. 398 – Seeing Things: Emitting, Reflecting, Ionizing Light
Astronomers gather electromagnetic radiation with the telescopes: mostly visible light. But sometimes they’ve got to be clever about where they look for these elusive photons. Light can get emitted, absorbed, reflected, and each method tells astronomers a little more about what they’re looking at.
Ep. 391: Entropy
Have you ever been doing thermodynamics in a closed system and noticed that there’s a finite number of ways that things can be arranged, and they tend towards disorder? Of course you have, we all have. That’s entropy. And here in our Universe, entropy is on the rise. Let’s learn about entropy in its specific, thermodynamic ways, and then figure out what this means for the future of the Universe.
Ep. 390: Occam’s Razor and the Problem with Probabilities
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.