Buzz Aldrin may have been the second person on the moon, but when we interview him on a recent Friday morning, he's in an easier-to-reach location: His home in the aptly named Satellite Beach, Florida. It's a rare day off in an otherwise busy schedule. He...
The dark, fingerlike features that creep down steep Martian slopes in warm weather continue to puzzle scientists. These "recurring slope lineae" (RSL), which have been spotted by NASA's Mars Reconnaissance Orbiter (MRO) at low and middle latitudes on the Red Planet, fade during cooler months but...
Most want to emplace supplies and equipment on Mars in advance, converting the atmosphere into propellant, air and water before humans arrive. Some want propellant depots in space on this end using lunar - or asteroid - derived materials. Some want massive rockets hurling astronauts from...