Dragon cargo spacecraft of the United States splashed down in the Pacific Ocean today. American space agency NASA said the spacecraft carried with it about 4,100 pounds of cargo. It said a variety of technological and biological studies return in Dragon, including hardware from the "Made in Space Fiber Optics" payload. <br/><br/>Results from this investigation could lead to the production of higher-quality fibre optic products both in space and on Earth. Mice from NASA's Rodent Research-6 study also return live to Earth for additional study. Dragon is the only space station resupply spacecraft currently able to return cargo to Earth. The spacecraft lifted off from Cape Canaveral Air Force Station in Florida on December 15 carrying about 4,800 pounds of supplies and scientific cargo.<br/><br/>