This Mobile Quarantine Facility (MQF) was one of four built by NASA for astronauts returning from the Moon. Its purpose was to prevent the unlikely spread of lunar contagions by isolating the astronauts from contact with other people. A converted Airstream trailer, the MQF contained living and sleeping quarters, a kitchen, and a bathroom. Quarantine was assured by keeping the air pressure inside lower than the pressure outside and by filtering the air vented from the facility. This MQF was used by Apollo 11 astronauts Armstrong, Aldrin, and Collins immediately after their return to Earth. They, together with a physician and a technician, remained in it for 88 hours while the MQF was transported on the aircraft carrier USS Hornet to the Pearl Harbor Naval Base in Hawaii and from there to nearby Hickam AFB. At Hickam, the MQF was loaded into the cargo hold of a C-141 aircraft and flown to Ellington AFB in Houston, Texas. The MQF, with the astronauts still on board, was then transported to the NASA Lunar Receiving Laboratory at Johnson Space Center where there were more spacious quarantine facilities. The astronauts were allowed to emerge from quarantine once scientists were sure they were not infected with "moon germs." NASA transferred the MQF to the Smithsonian Institution in 1974.