As a mark of respect for the memory of Neil Armstrong, President Obama has asked that all flags of the United States shall be flown at half-staff at the White House and upon all public buildings and grounds, at all military posts and naval stations, and on all naval vessels of the Federal Government in the District of Columbia and throughout the United States and its Territories and possessions until sunset on today. The flag shall be flown at half-staff for the same length of time at all United States embassies, legations, consular offices, and other facilities abroad, including all military facilities and naval vessels and stations. Neil Alden Armstrong was an American astronaut and the first person to walk on the Moon. He was also an aerospace engineer, U.S. Navy pilot, test pilot, and university professor.