CAPE CANAVERAL: Two veteran Russian cosmonauts floated outside the International Space Station on Wednesday to replace experimental equipment that is testing how materials and biological samples fare in the harsh environment of space.
Station flight engineers Yuri Malenchenko and Sergey Volkov left the station's airlock at 7:55 a.m. EST (1255 GMT) for what was expected to be a 5-1/2-hour spacewalk, a live broadcast on NASA Television showed.