Russian cosmonauts Pavel Vinogradov (L) and Alexander Misurkin take part in a spacewalk training exercise at the cosmonaut training centre in Star City outside Moscow February 5, 2013. Vinogradov, Misurkin and U.S. astronaut Christopher Cassidy are preparing for a mission to the International Space Station in March 2013. REUTERS/Sergei Remezov (RUSSIA - Tags: SCIENCE TECHNOLOGY TRANSPORT)