Apollo 10 was the full dress rehearsal for the first Moon landing — the mission that tested every procedure, every system, and every maneuver except the actual touchdown. Launched on May 18, 1969, atop a Saturn V from Launch Complex 39B (the first Apollo mission to use that pad), it carried Commander Thomas Stafford, Command Module Pilot John Young, and Lunar Module Pilot Eugene Cernan. Their spacecraft bore the call signs Charlie Brown (CSM) and Snoopy (LM), chosen to give the mission a lighter tone while carrying the weight of proving humanity could reach the lunar surface.

After a three-day coast to the Moon and successful Lunar Orbit Insertion, Stafford and Cernan separated Snoopy from Charlie Brown and descended to just 47,400 feet (8.4 nautical miles) above the lunar surface — close enough to scout Apollo 11’s landing site in the Sea of Tranquility. During the LM staging maneuver, the ascent stage began spinning wildly due to an incorrect abort guidance switch setting. Cernan exclaimed “Son of a bitch!” on live broadcast as Stafford fought to regain control — a moment of genuine danger that lasted only seconds but could have been fatal.

The crew also made history by broadcasting the first color television images from space, giving millions of viewers on Earth their first vivid look at our planet from afar. Apollo 10 validated every aspect of the lunar landing profile: rendezvous, docking, undocking, LM descent, staging, ascent, and re-docking. The mission confirmed that Apollo 11 could proceed with confidence.

On the return trip, the Command Module Charlie Brown reached a speed of 24,791 mph — the fastest any crewed vehicle has ever traveled, a record that stands to this day. The crew splashed down safely in the South Pacific on May 26, 1969, recovered by the USS Princeton. Two months later, Apollo 11 would land on the Moon in almost the exact spot Stafford and Cernan had surveyed from Snoopy’s windows.