Which booster was used to send the 1st American into orbit?
John Glenn John Herschel Glenn Jr. (July 18, 1921 – December 8, 2016) was a United States Marine Corps aviator, engineer, astronaut, and United States Senator from Ohio. In 1962 he became the first American to orbit the Earth, circling it three times.
J-2X The J-2X is a liquid-fueled cryogenic rocket engine that was planned for use on the Ares rockets of NASA's Constellation program, and later the Space Launch System. Built in the United States by Aerojet Rocketdyne (formerly, Pratt & Whitney Rocketdyne), the J-2X burns cryogenic liquid hydrogen and liquid oxygen propellants, with each engine producing 1307 kN of thrust in vacuum at a specific impulse ("I") of 448 isp . The engine's mass is approximately 2,470 kg (5,450 Lb), significantly heavier than its predecessors.