Originally, NASA's proposal for a manned mission to Mars cost about 450 billion dollars. Now, a single person proposes a mission that would cost roughly 1/20th of NASA's Reference Mission. His name is Robert Zubrin. The plan: Mars Direct! 

Zubrin is one of the members in the Mars Society, and has written a book, The Case for Mars, expressing his thoughts and discussing Mars Direct. Robert Z. says that Mars Direct will live off the land, unlike Nasa's proposal which has the astronauts carrying all of their supplies with them. Zubrin says the first launch of Mars Direct could well be in August of 2005. It would carry an Earth Return Vehicle (ERV) a 50 kilowatt nuclear reactor, an automated chemical factory, 7 tons of liquid hydrogen, and a few scientific rovers. These pieces would prepare themselves for the astronauts by the nuclear reactor making electricity and the chemical factory making water and fuel. This would take place in 2006.

In fall of 2007, a second ERV would be launched. Two weeks later, the first manned ship will take the four person crew would launch in the habitat module. Once in space, the fuel tank will be extended on tethers and spin the habitat around. This will create artificial gravity inside the habitat module.

 After staying and doing experiments on the red planet for several months, the crew would return in the first ERV. The second ERV would be left for the next crew, along with the chemical plant and nuclear reactor. In this way, each mission leapfrogs the next, so an ERV is left behind for the next crew.