Episodes

Ep. 283 Stellar Motions

Our Universe appears timeless and unchanging, the stars taking their nightly flight across the sky. But over long periods of time, you realize that our local region, and even the entire Milky Way is in constant motion. The constellations we see today would be very different millions or even thousands of years ago. Today we’ll discuss stellar motion, how astronomers detect it and how it’s useful.

Ep. 282 Seasons

Spring, Summer, Autumn and Winter. These are the seasons we experience here on Earth as our planet completes an orbit around the Sun. But what’s going on? Why do we experience such different temperatures and weather over the course of 365 days? Do other planets experience the seasons like we do?

Ep. 281 Explosions in Space

We’ve all seen the classic science fiction space explosions, full of flames and loud sounds. Beautiful on the screen but, totally lacking in any kind of… science. What’s wrong with science fiction? What would chemical and nuclear explosions really look like? What would we hear? And what are some natural explosions that nature detonates in space?

Ep. 280 Cosmological Constant

In order to allow for a static Universe, Albert Einstein introduced the concept of the Cosmological Constant Lambda to make the math work out. Once it was discovered that the Universe was actually expanding, he threw the number out calling it his “biggest blunder”. But thanks to dark energy, the Cosmological Constant is back.

Ep. 279 Hubble Constant

When Edwin Hubble observed that distant galaxies are speeding away from us in all directions, he discovered the reality that we live in an expanding Universe. Hubble worked to calculate exactly how fast this expansion is happening, creating the Hubble constant – which astronomers continue to refine and reference in their research.

Ep. 278: Animals in Space

We always think about humans in space, but the cold hard reality is that animals have always been first in space. First to fly, first to orbit, and sadly, first to die. Let’s learn about how our animal companions have been our trusty partners in space exploration, and let’s recognize their noble sacrifices over decades of experiments.

Ep. 277: Orbit

When an object is orbiting the Earth, it’s really falling. The trick, described in the Hitchhiker’s Guide to the Galaxy, is how to throw yourself at the ground and miss. There are several different kinds of orbits, and they are good for different reasons. From suborbital jumps to geostationary orbit, time to learn everything there is to know about going around and around and around.

Ep. 276: XMM-Newton

The Earth’s atmosphere keeps us alive and blocks x-ray radiation from reaching the surface. In order to understand the universe at the higher energy levels you need to launch a space telescope like the European Space Agency’s XMM-Newton Telescope. Let’s learn about the telescope named for the famous scientist.

Ep. 275: Isaac Newton

Isaac Newton has been called “the greatest and most influential scientist who ever lived.” That sounds about right. He unlocked our modern understanding of gravity and laws of motion, dabbled in optics, philosophy… even alchemy. He was also known to have a bit of a difficult personality. Let’s find out everything we can about Isaac Newton.

Ep. 274: Vesta

There’s some topics on Astronomy Cast that we wait until we are good and ready, until the science is all in. The Dawn mission has completed it’s mapping operations at asteroid Vesta and it’s now moving on to Ceres. This gives us a great opportunity to take a detailed look at this amazing asteroid, report on the science findings, and give you a preview of what’s coming next.