Streaking to Mars by 2020 or 2030 with several human beings aboard from low Earth orbit ang get there and back in a life sustainable period of time is one of the more challenging factors facing engineers and scientists this decade.
In more Earthly-terms, one can easily envision a race between a 3-cylinder subcompact car and a ‘muscle-car’ equipped with a super turbo-charged hemi across the United States. Assuming no operational failures, one might easily guess which vehicle would make the distance most rapidly.