What If You Skydived From the ISS?

410 kilometers (254 miles) above the Earth. That’s where the International Space Station floats. What if you happened to be all the way up here but suddenly fell...

What If We Built a City on Mars?

The next step in space exploration isn’t generations away. It’s happening right now. And our destination? That mysterious, desolate world next door, Mars...

What If We Moved Earth?

Some 5 billion years from now, the Sun will expand and become a red giant. And the Earth might be just in the way… If humans were still around then, would we leave...