Climate change is on our minds these days, with increasing wildfires, droughts and floods. What are the variables that play into a planet’s changing climate, and what can this teach us about the search for habitable planets across the Milky Way?
Our Hosts
Fraser Cain
Universe Today
Dr. Pamela Gay
CosmoQuest
Production by
- Richard Drumm, Audio Engineer
- Ally Pelphrey, Video Engineer
17 Seasons
700+ Episodes
Ep. 652: The Rocket Race Toward Reusability
Last week we talked about how single-use rocketry has changed over time, and the role it still plays in launching payloads into orbit and beyond. Today, we’ll address the stainless steel elephant in the room and talk about the shift to reusability.
Ep. 651: Artemis and the Decline of Single Use Rockets
On the day that we’re recording this, NASA’s Space Launch System is about to blast off. But everyone is expecting it’ll be delayed to October. When it does launch, it’ll be the most powerful rocket on Earth. Well, until Starship blasts off. Are we about to see the end of single-use rockets and enter the era of reusable rocketry?
Ep. 650: First Light for JWST
Well, this is it, we’re finally going to talk about the James Webb Space Telescope. After decades of development, delays and budget creep, the powerful infrared observatory is at its final home at the L2 Lagrange Point. Yesterday we saw the first scientific images from the telescope, and according to Pamela’s rules, we’re finally allowed to talk about it.
Recent Episodes
Ep. 382: Degenerate Matter
In some of the most extreme objects in the Universe, white dwarfs and neutron stars, matter gets strange, transforming into a material that physicists call “degenerate matter”. Let’s learn what it is, how it forms. Download the show [MP3] | Jump to Shownotes | Jump to...
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...
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...
Ep. 379: Fermi's Atom Splitting
When he wasn't puzzling the mystery of alien civilizations, Enrico Fermi was splitting atoms. He realized that when atoms were split, the neutrons released could go on and split other atoms, creating a chain reaction - and the most powerful weapons ever devised....
Ep. 378: Rutherford and Atoms
Physicists knew the interior of the atom contained protons, neutrons and electrons, but they didn't understand exactly how they were organized. It took Ernest Rutherford to uncover our modern understanding. Download the show [MP3] | Jump to Shownotes | Jump to...
Ep. 377: Thomson finds Electron
At the end of the 19th century, physicists were finally beginning to understand the nature of matter itself, including the discovery of electrons - tiny particles of negative charge that surround the nucleus. Here's how J.J. Thompson separated the electrons from their...
Ep. 376: The Miller-Urey Experiment
Evolution explains how life adapts and evolves over eons. But how did life originate? Chemists Miller and Urey put the raw chemicals of life into a solution, applied an electric charge, and created amino acids - the building blocks of life. Download the show [MP3] |...
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. Download the show [MP3] |...
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...
Ep. 373: Becquerel Experiment (Radiation)
Antoine Henri Becquerel discovered radioactivity completely by accident when he exposed a chunk of uranium to a photographic plate. This opened up a whole new field of research to uncover the source of the mysterious energy. Download the show [MP3] | Jump to Shownotes...
Ep. 372: The Millikan Oil Drop
In 1909 Robert Millikan devised an ingenious experiment to figure out the charge of an electron using a drop of oil. Let's talk about this Nobel Prize winning experiment. Download the show [MP3] | Jump to Shownotes | Jump to Transcript This episode is sponsored...
Ep. 371: Eddington Eclipse Experiment
At the turn of the 20th Century, Einstein's theory of relativity stunned the physics world, but the experimental evidence needed to be found. And so, in 1919, another respected astronomer, Arthur Eddington, observed the deflection of stars by the gravity of the Sun...
Ep. 370: The Kaufmann–Bucherer–Neumann Experiments
One of the most amazing implications of Einstein's relativity is the fact that the inertial mass of an object depends on its velocity. That sounds like a difficult thing to test, but that's exactly what happened through a series of experiments performed by Kaufmann,...
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...
Ep. 368: Searching for the Aether Wind: the Michelson–Morley Experiment
Waves move through a medium, like water or air. So it seemed logical to search for a medium that light waves move through. The Michelson-Morley Experiment attempted to search for this medium, known as the "luminiferous aether". The experiment gave a negative result,...
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...
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...
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...
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...
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? Download the show [MP3] | Jump to...