Orbiter (M)

"NASA had many successful space missions and programs, including over 150 unmanned missions and many space flight missions, most notably the space mission on Mars. NASA probes have been continually performing science at Mars since 1997, with at least two orbiters since 2001 and several Mars rovers. The orbiting Mars Odyssey and Mars Reconnaissance Orbiter will continue monitoring the geology and climate of the Red Planet and will continue searching for evidence of water and life presence, as they have since 2001 and 2006. The cockpit houses the pressurized crew module and it provides support for the nose section, nose gear and the nose gear wheel well and doors. The crew station consists of the flight deck, middle deck/equipment bay and an airlock. The flight deck permits the vehicle to be piloted from either seat and permits one-man emergency return while the middle deck contains provisions and stowage facilities for four crew sleep stations. The Orbiter is both the brains and heart of the Space Transportation System. About the same size and weight as a DC-9 aircraft, the Orbiter contains the pressurized crew compartment,the huge cargo bay and the three main engines mounted on its aft end and a midfuselage that supports the payload bay of the Orbiter."