The exploration of Mars has been a major part of the space programs of the United States, Russia, Europe and Japan.  Since 1947, there have been many proposals for a manned expedition to the red planet.  The National Aeoronautics and Space Administration included Mars in its Space Exploration Initiative of the 1980s.  The following are a few of the mission concepts that have been proposed over the years.

In 1947, Wernher von Braun proposed a Mars mission that consisted of a fleet of ten spacecraft, each one carrying 70 people.  After the success of the Apollo Program, he urged using Saturn V boosters to launch atomic-powered upper stages.  The upper stages would power two six-crew spacecraft on a dual mission.  In 1969, the Soviets proposed the Mars Expeditionary Complex that would take a crew of six to Mars and back.

The distance between the Earth and Mars is great.  Therefore, food and supplies would be necessary for a two to three year round trip.  The Design Reference and Mars Direct concepts resulted from this need.  NASA administrator Michael Griffin hinted in 2007  that his agency may be able to launch a manned mission to the red planet in 2037.  Another organization called MarsDrive advocates using current launch vehicle designs.  The most radical current proposal is to initially send one astronaut on a one way trip to Mars.  They may have trouble getting volunteers for that mission! 

A manned mission to Mars could be a dangerous, sub optimal use of government resources.  So say many critics, mindful of the major obstacles involved.  Such a mission would have additional challenges,  the effects of low gravity and exposure to cosmic rays among them. 

The European Space Agency and the United States have sent automated probes to Mars and have plans to send humans.  Russia can send humans into orbit around the Earth and have experience with long duration space flight.  However, some scientists contend that a manned flight to the red planet would take resources from other research.

In summary, there have been many proposals for a manned mission to Mars.  Wernher von Braun suggested a project to send 700 humans, Any expedition to the red planet would have to contend with many problems.  The United States, the European Space Agency and Russia probably have the technology and resources to launch a manned Mars mission.