Vostok 1 was the first spaceflight in the Vostok program and the first human spaceflight in history. Launched on April 12, 1961, the Vostok 3KA spacecraft carried Yuri Gagarin, a cosmonaut from the Soviet Union, into space. It marked the first time that a human had entered outer space, as well as the first orbital flight of a manned vehicle. Soviet engineers designed Vostok 1 as the centerpiece of its early space program, which was guided by Sergey Korolyov, under military supervision. The spaceflight itself consisted of a single orbit of the Earth, and according to official records, it took 108 minutes from launch to landing. As planned, Gagarin landed separately from his spacecraft, having ejected with a parachute 7 km (23,000 ft) above ground. The entire mission would be controlled by either automatic systems or ground control. Since medical staff and spacecraft engineers were unsure how a human might react to weightlessness, they locked the pilot’s manual controls. In an unusual move, they also placed a code to unlock the controls in an onboard envelope, for Gagarin’s use in case of emergency.

“Yuri’s Night” is an international celebration held on April 12 every year to commemorate space exploration milestones. The event is named for Yuri Gagarin, the first human to launch into space. Locations have included Los Angeles, Stockholm, Antarctica, the San Francisco Bay Area, Tel Aviv, Tokyo, and the International Space Station. The goal of Yuri’s Night is to increase public interest in space exploration and to inspire a new generation of explorers. Yuri’s Night was created by Loretta Hidalgo, George T. Whitesides and Trish Garner. The first Yuri's Night was held on April 12, 2001, on the 40th anniversary of human spaceflight. By 2009, Yuri's Night was celebrated all over the world, including Afghanistan.

Project Mercury was the first human spaceflight program of the United States. It ran from 1959 through 1963 with the goal of putting a human in orbit around the Earth. In pursuit of this goal, Mercury-Redstone 3 carried Alan Shepard as the first American in space, on May 5, 1961. John Glenn’s flight on the Mercury-Atlas 6 on February 20, 1962, was the first American flight to actually achieve the project’s central goal. Project Mercury included 20 unmanned launches, followed by two suborbital and four orbital flights with astronaut pilots. The National Advisory Committee for Aeronautics carried out early planning and research, but the program was officially conducted by its successor organization, the National Aeronautics and Space Administration (NASA). Mercury laid the groundwork for Project Gemini and the Apollo Program. The project name came from Mercury, a Roman mythological god often seen as a symbol of speed.