Some of you may have followed the voyage of Abby Sunderland, who attempted to become the youngest person to sail around the world solo. Things did not go as planned, however, and she suddenly needed to be rescued in the middle of the Indian Ocean last June. Recently she visited NASA and learned about the technology that enabled rescuers to locate her quickly; here is a video about it:
http://www.youtube.com/watch?v=-vEzY...layer_embedded