Episodes

Ep. 29: Asteroids Make Bad Neighbors

This week we’re talking about asteroids. And not just any asteroids, but Near Earth Objects. How do astronomers find these things, why are they buzzing around the Earth, what are the chances we’ll actually get hit, and what would happen if we did get hit? How could we stop them?

Ep. 28: What is the universe expanding into?

Come on, admit it, you’ve had this question. If the Universe is expanding from the Big Bang, what is it expanding into? What’s outside the Universe? Ask any astronomer and you’ll get an unsatisfying answer. We give you the same unsatisfying answer, but really explain it, so your unsatisfaction doesn’t haunt you any more.

Ep. 27: Questions Show #3

The questions are piling up, so it’s time to get through them. We’ve got a great collection this week. How can our eyes collect so many photons? What’s the speed of gravity? Shouldn’t the light from the cosmic microwave background radiation passed us by?

Ep. 25: The Story of Galaxy Evolution

Our Milky Way is a complex and majestic barred spiral galaxy. But 13.7 billion years ago it began, like all galaxies, from the elementary particles formed in the Big Bang. How did our galaxy grow from nothing to the hundreds of billions of stars we see today?

Ep. 24: The Fermi Paradox: Where Are All the Aliens?

We live in a mind bogglingly big Universe filled with countless stars. We know intelligent life evolved here on Earth. It must be common across the Universe, right? But if there’s life out there, how come we haven’t been visited by aliens yet? Why haven’t we even picked up signals from alien television stations? Where’s all the life?

Ep. 23: Counting Aliens With the Drake Equation

If you’re wondering how many extraterrestrials there are in our galaxy, you just have to use a simple equation developed by astronomer Frank Drake in 1961. Just find out how many stars there are, how many support life, how many advanced societies form, and a few other details and we’ll be set.

Ep. 22: Variable Stars

Our Sun has been around for billions of years, and will last for billions more. We’re lucky, it’s pretty stable and regular as stars go, only changing in brightness a little now and then. But there are stars out there that change dramatically; astronomers call them variable stars, and they demonstrate just how bizarre and dangerous the Universe can be.

Ep. 21: Questions Show #2

Our episode on black holes generated many many questions from listeners. We dip into this bottomless pool of questions and start dealing with them. Are really big black holes like the Big Bang? How can black holes evaporate? What would it look like to stand on a black hole? And just how large would a rock have to be before its gravity is so strong that a human can’t escape?