Cafe

The solstice alignments of Stonehenge, explained.

So you know a bit about the Big Bang - but did you know that you can physically see or hear it in your every day life? Find out how 'static' often contains remnants from this monumental event.

How did the universe begin -- and how is it expanding? CERN physicist Tom Whyntie shows how cosmologists and particle physicists explore these questions by replicating the heat, energy, and activity of the first few seconds of our universe, from right after the Big Bang.

When you stare up at the night sky, you might think that the universe is really black, but that's just because our eyes aren't sensitive enough to see the billions and billions of multicolored stars out there. Ever wonder why certain stars are certain colors? And what color is our sun, really? If we looked at enough stars, could we figure out the average color of the universe?

Counting stars from the shore of the cosmic ocean...

Could we stop an asteroid on a collision course for Earth?

Miss The Solar Eclipse This Year? Watch This Incredible Footage Of It!

Only one side of the Moon is visible from Earth because the Moon rotates about its spin axis at the same rate that the Moon orbits the Earth, a situation known as synchronous rotation or tidal locking.

The Greeks had a simple and elegant formula for the universe: just earth, fire, wind, and water. Turns out there's more to it than that -- a lot more. Visible matter (and that goes beyond the four Greek elements) comprises only 4% of the universe. CERN scientist James Gillies tells us what accounts for the remaining 96% (dark matter and dark energy) and how we might go about detecting it.

Why does February only get 28 days when all the other months get 30 or 31? The answer is part superstition, part politics, and parts astronomy.

The true scale of our cosmic neighborhood. Whoa.

What it's like to see the Earth from orbit.

The fact that no one knows the answer to this question is what makes it exciting. The story of physics has been one of an ever-expanding understanding of the sheer scale of reality, to the point where physicists are now postulating that there may be far more universes than just our own. Chris Anderson explores the thrilling implications of this idea.

During Expedition 40 in the summer of 2014, NASA astronauts Steve Swanson and Reid Wiseman - along with European Space Agency astronaut Alexander Gerst - explored the phenomenon of water surface tension in microgravity on the International Space Station. The crew "submerged" a sealed GoPro camera into a floating ball of water the size of a softball and recorded the activity with a 3-D camera.

After a ten-year journey, Rosetta and Philae had finally reached their destination, Comet 67P/Churyumov-Gerasimenko. Rosetta spent many weeks studying the comet, sending lots of information back to Earth. But where was Philae going to land? Eventually the scientists on Earth found the best place on the comet for Philae to land. Soon it was time to make the final preparations for Philae's great adventure. Both spacecraft couldn't wait any longer. The whole world would be watching as Rosetta and Philae prepared for their biggest challenge yet.