... Credit Copyright: NASA , Gemini Project , James McDivitt Explanation: Fifty years ago , on June 3, 1965, Edward White stepped out of the orbiting Gemini 4 spacecraft to become the first US astronaut to walk in space . White is captured in this photo taken by mission commander James McDivit from inside the capsule as White's spacewalk began over the Pacific Ocean on Gemini 4's third orbit . ... A gas powered manuevering gun is held in his right hand. ... NASA Official: Jay Norris. ...