Kelly found himself repeatedly wiping away excess grease while lubricating the snares on the tip of the International Space Station's big robot arm. In addition to the routine lube work, they routed cable for a future docking port, removed insulation from an electronic switching unit, and covered an antimatter and dark matter detector. In the wee hours of Thursday morning, just after midnight Eastern time, Kelly will break the American record for NASA's longest single space shot. Russian Mikhail Kornienko is also part of the one-year experiment in preparation for eventual Mars expeditions, although it will fall shy of the 14-month world record held by a fellow cosmonaut, Valery Polyakov, who lived on Russia's old Mir space station in 1994 and 1995. Before Wednesday's spacewalk, Kelly's identical twin, Mark, a retired astronaut, urged his brother to be careful but still have fun. Scientists wanted the device covered with a thermal blanket to keep it cooler and prolong its life.