Astronomy Cast

AstronomyCast 279: The Hubble Constant, by Fraser Cain & Dr. Pamela Gay

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.

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?

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?

AstronomyCast 278: Animals in Space, by Fraser Cain & Dr. Pamela Gay

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.

AstronomyCast 277: Orbit, by Fraser Cain & Dr. Pamela Gay

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.

AstronomyCast 276: XMM Newton, by Fraser Cain & Dr. Pamela Gay

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.