Apollo 10

Apollo 10 Command and Service Module with Moon in the background photographed from the Lunar Module

The fourth manned flight of the Apollo Projectand the final rehearsal for the first manned lunar landing. 

Apollo 10’s main purpose was to test rendezvous and docking operations between the Command and Service Module (CSM) and the Lunar Module (LM) in lunar orbit. Having entered orbit around the Moon, astronautsStafford and Cernan transferred to the LM, undocked it, and flew within 15,200 meters of the Moon's surface. After the LM descent stage had been jettisoned prior to re-docking, the orientation of the ascent stage began to change unexpectedly due, it turned out, to an incorrectly placed switch. The astronauts took manual control of the LM and were able successfully to rendezvous and re-dock with the CSM. The Apollo 10 crew achieved the highest speed ever attained by human beings – 39,896 km/h. This was also the highest speed of entry into Earth's atmosphere by any spacecraft until it was surpassed by the Stardust probe. 

Commander	Thomas Stafford
Lunar Module pilot	Eugene Cernan
Command Module pilot	John Young
Call signs	CM: Charlie Brown, LM: Snoopy
Launch	May 18, 1969; 16:49:00 UT (12:49:00 p.m. EDT) Kennedy Space Center Launch Complex 39B
Mission duration	192 hr 3 min. 23 sec.
Splashdown	May 26, 1969; 16:52:23 UT (12:52:23 p.m. EDT)
Retrieval site	Pacific Ocean 15° 2' S, 164° 39' W

Highlights

• Two Apollo 10 astronauts descended to within eight nautical miles (14 km) of the Moon's surface, the closest approach ever, at that time, to another celestial body
• The only Apollo mission to launch from Launch Complex 39B
• Demonstration of color TV camera