Template:POTD/2012-08-14
Tracy Caldwell Dyson in the Cupola module of the International Space Station, observing the Earth below during Expedition 24. Caldwell Dyson is an American chemist and astronaut. She was selected by NASA in 1998 and made her first spaceflight in August 2007 on the STS-118 mission aboard Space Shuttle Endeavour.Photo: NASA/Tracy Caldwell Dyson