Who flew on more Space Shuttle missions, meteorologist Piers Sellers or chemical engineer Lodewijk van den Berg?
Piers Sellers Piers John Sellers OBE (11 April 1955 – 23 December 2016) was a British-American meteorologist, NASA astronaut and Director of the Earth Science Division at NASA/GSFC. He was a veteran of three space shuttle missions.
Multi-Application Survivable Tether The Multi-Application Survivable Tether (MAST) experiment was an in-space investigation designed to use CubeSat spacecraft connected by tethers to better understand the survivability of tethers in space. It was launched as a secondary payload on a Dnepr rocket on 17 April 2007 into a 98°, 647 x 782 km orbit. The MAST payload incorporated three picosatellites, named "Ralph," "Ted," and "Gadget," which were intended to separate and deploy a 1 km tether. The experiment hardware was designed under a NASA Small Business Technology Transfer (STTR) collaboration between Tethers Unlimited, Inc. (TUI) and Stanford University, with TUI developing the tether, tether deployer, tether inspection subsystem, satellite avionics, and software, and Stanford students developing the satellite structures and assisting with the avionics design.