Today we tackle more thrilling mysteries of the Universe. And by tackle, we mean, acknowledge their puzzling existence. Some mysteries will be solved shortly, others will likely trouble astronomers for centuries to come. Join us for part 2. ...

All finished with the Milky Way, it’s time to move on to the biggest mysteries of all. The mysteries of the Universe. Let’s wonder about dark matter and dark energy, and the very nature of reality itself. ...

Deep field image by Hubble What if our universe was just one in an infinite number of parallel universes; a possible outcome from the specific predictions of quantum mechanics. The idea of multiple universes is common in science fiction, but is there any actual science to back this theory up? ...

Evolution of the large scale structure of the Universe. Image credit: NASA This week we’re going to think big. Bigger than big. We’re going to consider the biggest things in the Universe. If you could pull way back, and examine regions of space billions of light-years across, what would you see? How is...

We continue our journey through the electromagnetic spectrum with X-rays. If you’ve ever broken a bone, you probably know how X-rays are most commonly used. While doctors use X-rays to study the human body, and astronomers use X-rays to study some of the hottest places in the Universe. So let’s...

M81 in ultraviolet. Image credit: NASA Our next visit in this tour through the electromagnetic spectrum is the ultraviolet. You can’t see it, but anyone who’s spent a day out in the hot sun without sunblock has sure experienced its effects. Ultraviolet radiation is associated with the birth of...

Hubble Deep Field. As astronomers discovered that we live in a great big universe, they considered a fundamental question: is the universe the same everywhere? Imagine if gravity was stronger billions of light years away… Or in the past. It sounds like a simple question, but the answer has been tricky...

WMAP image of the Cosmic Microwave Background Radiation. We did a wildly popular three part series about the center, size and shape of the Universe. But every good trilogy needs a 4th episode. This week we look at age of the Universe. How old is the Universe, and how do we know? And how has this number...

Hopefully you’ve all recovered from part 1 of this set, where we make you sad about the future of the humanity, the Earth, the Sun and the Solar System. But hang on, we’re really going to bring you down. Today we’ll look far far forward into the distant future of the Universe, at...

This is a show we wanted to do since we started Astronomy Cast but we always thought it was too early. We wanted you to know that we’re positive, happy people with enthusiasm for astronomy and the future. It’s time for some sadness. It’s time for a grim look to see what the future holds...