The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight in Houston, Texas (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U.S. president and Texas native, Lyndon B. Johnson, by an act of the United States Senate on February 19, 1973.
JSC consists of a complex of 100 buildings constructed on 1,620 acres (660 ha) in Clear Lake. The center is home to NASA's astronaut corps, and is responsible for training astronauts from both the U.S. and its international partners. It also houses the Christopher C. Kraft Jr. Mission Control Center, which has provided the flight control function for every NASA human spaceflight since Gemini 4 (including Apollo, Skylab, Apollo–Soyuz, and Space Shuttle). It is popularly known by its radio call signs "Mission Control" and "Houston".