Buzz Aldrin was Apollo 11's lunar module pilot, helping land astronauts on the Moon in 1969.
Aldrin descended to the lunar surface with commander Neil Armstrong in the lunar module Eagle on July 20, 1969. He became the second person to walk on the Moon, following Armstrong, and spent about two hours and 15 minutes outside the lunar module.
Michael Collins was the mission's command module pilot and remained in lunar orbit aboard Columbia. A common mix-up is to call Aldrin Apollo 11's commander; that role belonged to Armstrong. Aldrin later became especially associated with describing the lunar view and with the famous photograph Armstrong took of him on the surface.