ISS Star Trail Photography By Donald Roy Pettit

During Expedition 6 in 2002/2003, Pettit used spare parts found throughout the Station to construct a barn door tracker; the device compensates for the movement of the ISS relative to the Earth's surface, permitting sharper high resolution images of city lights at night from the orbiting space station.
In November 2008, Pettit invented a zero-g coffee cup, which used the wetting angle to carry the coffee along a crease to permit drinking and avoid the necessity of a straw. This zero-g cup was featured in the May 2009 National Geographic Magazine issue, along with his notes on the relation of the internal cup angle to the contact wetting angle for various construction materials.