The Apollo 10 crew from left, Eugene Cernan, John Young and Thomas
Stafford are photographed while at the Kennedy Space Center. In the
background is the Apollo 10 space vehicle on Launch Pad 39 B.

Apollo 10 was the fourth manned mission in the  Apollo space program. Launched
on May 18, 1969, it was the F mission: a "dress rehearsal" for the first Moon landing, testing all of the components and procedures, just short of actually landing. The
Lunar Module came to within 8.4 nautical miles of the lunar surface, the point where
the powered descent to the lunar surface would begin. Its success enabled the first landing to be attempted on Apollo 11 in July, 1969.

According to the 2002 Guinness World Records, Apollo 10 set the record for the
highest speed attained by a manned vehicle at 24,791 mph during the return from
the Moon.