ORION CREW EXPLORATION VEHICLE
UPDATE: 11 October 2010. In a major policy speech, Barack Obama formally ended the Constellation Program. He instructed NASA to begin work on a rocket for deep space exploration. He also directed that commercially based means be used to launch ISS crew members. The Orion itself has not been cancelled, but past work is being applied to development of a modified version known as the Multi-Purpose Crew Vehicle (MPCV) with a primary goal of serving destinations beyond low Earth orbit.
While Orion looks much like the old Apollo spacecraft, it is significantly larger with a diameter of 16.5 feet (5 meters) and can carry a crew of up to six. The software and avionics are based upon the latest in aviation technology. The Apollo-like configuration was chosen because of the proven ability of the heat shield, especially for re-entry after lunar missions. Initial requirements called for Orion to be able to land on both ground and water (water being necessary in the event of a launch abort). The latest requirements have dropped the ability to land on ground.
A crew of four was proposed for lunar missions, with a crew of six for missions to the International Space Station or later missions to Mars. For lunar missions, Orion would have been capable of bringing back 220 pounds (100 kg) of payload.
A launch abort system will sit atop the Orion to pull the spacecraft and crew to safety during an emergency on the launch pad or during ascent. Power and propulsion systems are in the service module located directly below the crew module.
For ISS or other low-earth orbit missions, Orion was to be launched by the Ares I. For lunar missions, both Ares I and the Ares V would have been used. Orion would have been capable of remaining docked with the ISS for up to six months. Orion was also be capable of carrying pressurized cargo on unmanned missions.
As mentioned, for lunar missions, both the Ares I and the Ares V would have been used. The Ares V would launch first, carrying the Earth Departure Stage and Lunar Module into orbit. Next, the Ares I would launch the Orion, which then mated with the Lunar Module and Earth Departure Stage.
The first manned Orion mission was projected for September 2013. The first manned lunar mission was forecast for 2020.
|View an Lunar Surface Animation video (NASA)
The Orion crew exploration vehicle and its service module orbit the moon with disc-shaped solar arrays tracking the sun to generate electricity. (NASA)