Apollo 11’s landing is documented in primary NASA materials created at the time of the mission, including the Apollo 11 Flight Plan and the Apollo 11 Mission Report (NASA). These records lay out the mission timeline and explicitly describe the powered descent, touchdown, and subsequent surface activities by the crew.
The event is also corroborated outside NASA by major independent institutions and archives. The Smithsonian’s National Air and Space Museum summarizes the mission as the first time humans walked on the Moon on July 20, and contemporaneous media coverage (including Associated Press footage) recorded the event as it occurred, matching the mission timeline described in NASA documentation.