Answer: Mercury Atlas 9
On May 16, 1963, NASA astronaut L. Gordon Cooper, Jr. was in a fairly tight spot. Cooper was the only crew member aboard Faith 7 an orbital spacecraft hauled up by an Atlas LV-3B rocket as part of the space mission Mercury Atlas 9 ̵
1; the first and only one-day mission in the Mercury program.
During much of Cooper's time in space, orbiting the Earth nearly two dozen times over a day and a half, the mission was straightforward. However, as the time to reenter approached, problems arose. On the 20th orbit, Cooper lost height measurements, and on the 21st orbit, a short circuit failed the automatic stabilization and control systems without power. In addition to the electromechanical errors, the carbon dioxide level in the cabin and its spacesuit increased.
Cooper kept his wits and used his wristwatch to time control his manual control of retrorockets, his knowledge of astronomy, to use the stars as reference points, and to use a grease pen to draw lines on the window of the capsule To connect with the constellations during the flight, he made an absolutely beautiful landing in the textbook. Under Cooper's expert handling, Faith 7 splashed 4 miles from the world class salvage ship, the USS Kearsarge into the ocean. This landing was the most accurate capsule landing in NASA history, despite the lack of automatic controls.
Cooper's cool flight marked the last Mercury mission and the last manned mission until the launch of Gemini 3 in the spring of 1965.