“"4 hours"”
Veteran Mercury astronaut Virgil I. "Gus" Grissom and first-time flyer John W. Young rode a Titan II rocket into orbit aboard a spacecraft Grissom named Molly Brown—a wry reference to his ill-fated Mercury capsule, Liberty Bell 7, which had sunk after splashdown. Gemini III was the first crewed flight of the new program, and it had to prove that a two-man spacecraft could maneuver. Over three orbits lasting 4 hours and 52 minutes, Grissom and Young fired their OAMS thrusters to lower their orbit, shift inclination, and set up reentry, becoming the first humans to change a spacecraft's orbital path deliberately. The mission also tested the worldwide tracking network, reentry guidance, and spacecraft recovery. A contraband corned-beef sandwich—smuggled aboard by Young—provided a moment of levity and a minor disciplinary note in the postflight debrief, but the engineering results were unambiguous: Gemini worked. The capsule landed 52 miles short of the target point because of lower-than-expected lift during reentry, but Grissom and Young were recovered by the USS Intrepid in good condition. Gemini III was the last American human spaceflight controlled from Cape Canaveral; with Gemini IV, command shifted permanently to the new Mission Control Center in Houston.
Gemini 3 was the first crewed flight to deliberately change its own orbit, proving spacecraft could maneuver — a prerequisite for rendezvous and the Moon.