In the early 1900s, Henrietta Leavitt made one of the most important discoveries in the history of astronomy: a yardstick to measure distances to faraway stars. Using this tool, scientists eventually transformed our understanding of the universe. They realized space was expanding, that this expansion was accelerating, and that ultimately, everything will end ... Show More
Apr 15
The Hitchhiking Microbe’s Guide to the Galaxy
Can microbes travel through space on meteorites? It’s an idea called “lithopanspermia,” and to work out if it’s even feasible, some researchers decided to shoot microbes — with a gun. Guests: K.T. Ramesh, professor of science and engineering at Johns Hopkins University; Lily Zhao ... Show More
26m 18s
Apr 13
Why did we go back to the moon?
For the first time in over 50 years, humans have gone to the moon and back. And this time, NASA says we're going to stay. NASA's planning for more missions, a permanent moon base, and even a mission to Mars. But there's a pretty big question hanging over all these dreams: Can hum ... Show More
31m 33s