This is SCIENCE FRIDAY. I'm Ira Flatow. Last week, the SpaceX Dragon capsule splashed down in the Pacific, wrapping up a glitch-free journey to the International Space Station. It was an historic first. The Dragon is really the only private spacecraft to have made the trip. This time there was only cargo aboard. But it will be - not be long before astronauts are hitching rides on the Dragon? That's what SpaceX is planning for next, and they hope to have seats ready for travelers by 2015. So you can mark that in your calendar.
You're listening to SCIENCE FRIDAY. I'm Ira Flatow. Our next story is about one person's garbage being another person's treasure. You know how that works. Well, this one is a very interesting story. Last year, the National Reconnaissance Office, they operate America's spy satellites, well, the National Reconnaissance Office called up NASA with an offer: Would NASA like a couple of old spy telescopes? We don't need them. Could you do anything useful with them? We'll give them to you.
This is SCIENCE FRIDAY. I'm Ira Flatow. If you look up in the sky at night, especially later this year, you can spot the Andromeda Galaxy, it's a small cloudy smudge in space. It's our galaxy, the Milky Way's closest galactic neighbor, about two and a half million light years away.
Alan Alda challenged scientists to explain what a flame is to an 11-year-old. Three months and more than 800 entries later he is back with the winner of the contest. Ira Flatow and guests discuss the winning entry and why the contest was an effective exercise in science communication.
Reporting in the journal Nature Communications,researchers write that they were able to track down the cells causing clogged arteries. Dr. Jill Helms, co-author on the study, discusses why stem cells are to blame and how the study could lead to more effective treatments.