a crew of four private astronauts made history in the early hours of Thursday when they opened the hatch of their SpaceX Dragon capsule and conducted the first commercial spacewalk the spacewalk the riskiest part of the 5-day Polaris Dawn Mission kicked off at 6:12 a.m. ET when oxygen started flowing into the astronaut space suits only two of the four crew members actually exited the vehicle but all four had to Dawn the new SpaceX made suits because the Dragon capsule doesn't have an airlock that meant the entire spacecraft had to be depressurized a spacewalk sometimes called extra vehicular activity is when astronauts leave the relative safety of their spacecraft for the vacuum of space in the history of human space flight spacewalks have only ever been performed by government astronauts who use them as an opportunity to do repairs perform maintenance or to conduct scientific experiments space walks performed by NASA astronauts typically last between 5 and 8 hours