The USA's future plans for space travel were outlined in the Vision for Space Exploration, stated by U.S. President George W. Bush on 14 January 2004. Throughout late 2004 and early 2005, Congress passed legislation showing their support for the Vision, including a $16.2 billion US Dollar (USD) NASA budget and a bill that explicitly endorses the project. Several years later, President Barack Obama canceled parts of the plan, including the Constellation program that was designed to take astronauts back to the Moon, but insisted that the administration was still committed to manned space flight.
The highlight of the original plan was a return to the Moon with robotic and crewed missions, including plans for a long-habitation moon base to be occupied by 2024. The base would have astronauts staying for six months at a time, similar to a typical stay on a space station in low earth orbit. The Moon base was seen as a long-term stepping stone for Mars missions.
The Vision for Space Exploration included numerous goals and anticipated milestones. First were robotic missions to the Moon, planned for sometime between 2008 and 2010. In 2010, the Space Shuttles were retired, and the United States no longer had a means of human space travel. The country is dependent on the Russian Soyuz spacecraft for trips into space. The International Space Station is expected to be completed by 2012.
Despite the cancellation of the Constellation program, the Orion spacecraft, capable of carrying four to six astronauts, is scheduled to be tested by 2014, although it's not expected to be used before 2020. It's expected to be used as an escape capsule from the International Space Station rather than as a spacecraft capable of traveling to the station. In 2010, President Obama announced plans for the Shuttle-Derived Heavy Lift Launch Vehicle (HLV), to be completed by 2015, and plans to send astronauts to an asteroid. Missions to Mars are still predicted, likely sometime after 2030.
It is obvious why the original primary focus of the US space travel vision was the Moon: it is the closest celestial body, with many of the basic resources necessary to sustain life and an economy, not to mention an excellent view. Some people still believe that the US should go back to the Moon, and that humanity will eventually settle there. With luck and the continued acceleration of progress in the enabling technologies, travel to more planets is still hoped for.
