Orion is a spacecraft built by Lockheed Martin for NASA. Each Orion spacecraft is going to carry up to four astronauts. The spacecraft was first planned to be launched by the Ares I launch vehicle, for the Constellation Program. On 11 October 2010, the Constellation Program was cancelled, and the Orion vehicle is to be launched first on top of a Delta IV rocket. Later ones will use the Space Launch System.
Orion would launch from Launch Complex 39 at Kennedy Space Center, the same launch site used by the Space Shuttle and the Saturn V. While shuttle operations continued from launch pad 39A, 39B was readied for Ares launches. The first crewed Orion flight is set for 2016. Later flights would visit the International Space Station. If commercial space transportation services are not used, Orion would handle building flights to the station. After that, Orion may become a key part of human missions beyond low Earth orbit which may include missions to Near-Earth objects, the Moon and Mars.
The U.S. Federal Government thought of ending the Constellation program in February 2010. A new law was passed on October 11, to remake the Constellation program and put more efffort into visiting Near-earth objects and Mars. Orion is costing 175 million dollars, according to the space politics blog.