May 18th, 1969, Apollo 10 launched away from Kennedy Space Center, crewed by: Thomas P. Stafford, John W. Young and Eugene A. Cernan on the fourth manned mission in the United States Apollo space program. A literal "dress rehearsal" for the first Moon landing, testing all components and procedures and maneuvers just short of actually landing.
The Lunar Module (LM) came to within a mere 8.4 nautical miles of the lunar surface, the point where the powered descent to the
lunar surface would begin. The success of the Apollo 10 "dress rehearsal"
mission would enable the continuation of the program, and hopfully allow for first landing to be attempted on Apollo 11 in July, 1969.
Because the mission required the lunar module to skim the moon's surface and "snoop around" scouting the Apollo 11 landing site, the crew named the lunar module "Snoopy." Naturally, the Apollo command module was named "Charlie Brown."
It seems that NASA had trust issues when it came to their Astronauts...and took special precautionary measures to ensure Stafford and Cernan would not be tempted, or even given the possibility to attempt to make the first landing.
Cernan said "A lot of people thought about the kind of people we were: 'Don't give those guys an opportunity to land, 'cause they might!' So the ascent module, the part we lifted off the lunar surface with, was short-fueled. The fuel tanks weren't full. So had we literally tried to land on the Moon, we couldn't have gotten off."
Perhaps as an admission, and indicator of possible intent, In his own memoir, Cernan wrote "Our lander, LM-4...was still too heavy to guarantee safe margins for a moon landing."
The crew of Apollo 10 may not have been the first to land on the surface of our Moon, however tempted they may have been...but, they did set the world absolute record for the highest speed attained by a manned vehicle at 11.08 km/s or Twenty Four Thousand Seven Hundred and Ninety One miles per hour during their return from the Moon on May 26th, 1969.
"Curiosity is the essence of human existence. 'Who are we? Where are we? Where do we come from? Where are we going?'... I don't know. I don't have any answers to those questions. I don't know what's over there around the corner. But I want to find out." - Gene Cernan
Don't feel bad for ol' Gene, he did return to the Moon commanding his own crew on Apollo 17, and on December 11th 1972, Commander Gene Cernan stepped down the ladder of the Lunar Lander, and walked on the surface of our Moon.
"I walked on the Moon. What can't you do?" - Gene Cernan