In the [[United States]], there is no legal definition for "space;" however, a crew member of a government vehicle is considered an astronaut if they have been above 50 miles in altitude above mean sea level. This definition of astronaut leads to a common acceptance of "space" in legal documents as beginning at 50 miles in altitude (~ 80.5 km). | In the [[United States]], there is no legal definition for "space;" however, a crew member of a government vehicle is considered an astronaut if they have been above 50 miles in altitude above mean sea level. This definition of astronaut leads to a common acceptance of "space" in legal documents as beginning at 50 miles in altitude (~ 80.5 km). |