How Long Was Mars Wet?

Planetary scientist Briony Horgan and her team want to know how long liquid water flowed on the surface of the Red Planet before that world froze. Long enough for life to appear and thrive? New work comparing Earth’s extremes may have provided clues. There’s gas in space, and some of it is inside astronauts. Bruce Betts shares the uncomfortable truth in this week’s What’s Up. Also, space headlines from The Downlink. Learn more about this week’s guest and topics at: http://www.planetary.org/multimedia/planetary-radio/show/2019/1023-2019-briony-horgan.html See omnystudio.com/listener for privacy information. See omnystudio.com/listener for privacy information.