Apollo 10, crewed by Thomas Stafford (Commander), John Young (Command Module Pilot) and Gene Cernan (Lunar Module Pilot), was launched from KSC on May 18, 1969. It was a rehearsal for the Apollo 11 moon landing mission. Expanding on tests conducted in Earth orbit for Apollo 9, th Apollo 10 astronauts brought a fully functional lunar module to the Moon and flew it within 16 kilometers of the surface, photographing candidate landing sites in Mare Tranquillitatis. The objective of this mission was to test all components and procedures, but not the actual landing on the Moon.
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| Photo: Astronaut-geologist Harrison Schmitt brief the Apollo 10 crew on the lunar topographic features they will see during their moon-landing dress rehearsal flight. |
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| Apollo 10 crew signed Heritage Crafts launch cover with a Kennedy Space Center machine cancel dated May 18, 1969, directly from the family collection of astronaut Richard Gordon. Signed by Eugene Cernan, John Young and Tom Stafford. From the Family Collection of Astronaut Richard Gordon. - Heritage Auctions |
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| Photo: The Apollo 10 crew, Gene Cernan, Thomas Stafford, John Young, chosen characters from Charles Schulz's "Peanuts" comic strip, "Snoopy" and "Charlie Brown" as their mission's call signs and mascots. |
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| Apollo 10 official NASA cachet on cover, postmarked on May 18, 1969, with a Kennedy Space Center machine cancel. Signed by Tom Stafford, John Young and Gene Cernan. - RRAuction |
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| Photo: "Astronaut Thomas Stafford reached out to pat the nose of a stuffed "Snoopy" dog held by a secretary, Miss Jayme Flowers, after suiting up for the Apollo 10 launched at Cape Kennedy, Sunday. AP Wirephoto. May 18, 1969." |
It took the crew three days to reach the moon and get into lunar orbit where they went through all the phases leading up to a lunar landing.
After the spacecraft reached lunar orbit, astronaut John Young remained in the Command and Service Module (CSM) while astronauts Thomas Stafford and Gene Cernan flew the Apollo Lunar Module (LM) to within 14.4 kilometers (7.8 nmi) of the lunar surface, the point at which powered descent for landing would begin on a landing mission.
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| NASA local post cover postmarked at Houston on May 22, 1969, the day when Apollo 10 lunar module descended to wtithin 9.4 miles of the moon's surface. |
On May 22, 1969, Thomas Stafford and Eugene Cernan in the LM Snoopy separated from the command module, nicknamed Charlie Brown, where John Young remained alone.
Then Snoopy was inserted into a descent orbit, stopping less than 50,000 feet above the surface. From that altitude they saw the moon’s mountains and craters in more detail than any human had before.
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| Photo: Crater Taruntius H taken from the lunar module. |
When the test flight completed, Snoopy was divided into two sections; the descent stage, which on later landing missions would remain on the lunar surface, was allowed to crash into the moon, while the ascent stage was jettisoned such that it entered into orbit around the sun.
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| Cover with a printed cachet of Snoopy on the moon, postmarked at Satellite Beach on May 22, 1969. |
After four orbits, the Apollo LM rejoined Young in the CSM. While in lunar orbit, the Apollo 10 crew spent the rest of the time on landmark tracking and photography.
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| Photo: Crater Censorinus taken from the command module. |
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| Photo: The back side of the moon photographed by Apollo 10. |
On the 31st orbit, the Service Propulsion System (SPS) restarted. Apollo 10 was on the back side of the moon when it was injected into a trans-Earth trajectory.
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| Photo: View of the moon taken after trans-Earth insertion when the Apollo 10 spacecraft was high above the lunar equator, May 24, 1969. The large dark area near the center of the photograph is the Sea of Tranquility - the projected landing site for Apollo 11. |
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| Photo: "Astronaut Shaves with Razor on Way Home. John W. Young uses a safety razor and lather to shave during the return flight of Apollo 10. In background is Flight Commander Tom Stafford. The shave was a space first. All three astronauts were clean shaven when they landed. NASA photo via AP Wirephoto." |
On May 26, 1969, Apollo 10 splashed down in the Pacific Ocean, 400 miles east of American Samoa, and was recovered by the recovery ship USS Princeton.
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| Apollo 10 splashdown in the Pacific Ocean. Top: NASA local post cover postmarked May 26, 1969, at Houston. Bottom: Cover postmarked May 26, 1969, at Cape Canaveral. |
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| Photo: Apollo 10 crew leaving command module, Charlie Brown. |
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| Apollo 10 crew and capsule recovery. Cover postmarked May 26, 1969, at Cape Canaveral. |
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| Photo: The scene in Mission Control at the Manned Spacecraft Center in Houston after the successful splashdown of Apollo 10 spacecraft. |
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| Photo: USS Princeton, the prime recovery ship for the Apollo 10 astronauts. |
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| Apollo 10 USS Princeton captain's cover, machine cancelled May 26, 1969. |
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| Photo: The Apollo 10 crew, Eugene Cernan, John Young and Tom Stafford, and commanding officer Captain Carl Mann Cruse aboard USS Princeton. |
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| Apollo 10 USS Princeton recovery ship cover with Beck rubber stamped cachet. Signed by John Young, Gene Cernan and Tom Stafford. The signatures were obtained from NovaSpace signing sessions. - RegencyStamps |
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| Apollo 10 USS Princeton recovery ship cover with Beck rubber stamped cachet. Signed by NASA recovery team leader Charles Filley, commander of the Pacific-based Task Force 130 Rear Adm. Frederick E. Bakutis, astronaut Gene Cernan, commanding officer Captain Carl Mann Cruse, helo recovery pilot Cdr. Charles B. Smiley. |
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| Apollo 10 USS Princeton recovery ship cover with a very rare hand cancel and a black Beck rubber stamped cachet. Beck stamped cachet in magenta with USS Princeton machine cancel is commonly found on covers. |
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| Photo: Apollo 10 crew, just back from the trip around the moon, talked with the Apollo 11 crew, which will land on the moon. |
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| Photo: Apollo 10 crew at a post flight news conference on June 7, 1969. |
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| Photo: Apollo 10 crew return to launch site on June 11, 1969. |
