Known throughout the space community for their Skylon jets (which are still in development), Reaction Engines has proposed what appears to be a reasonable path to help humanity reach the red planet within our life time.
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While the plan for the most part is rather sound, the one fatal area is the length of time it takes to reach the crimson world as solar radiation might fry the astronauts brains before they even get an opportunity to land.
Unless artificial magnetic fields can be constructed around the space craft, future explorers may have to wait until VASIMR engines become a reality (in order to cut the travel time from 6 months to 39 days).
Trek time aside, Reaction Engines does have the wisest approach when it comes to establishing outposts upon Mars (i.e. sending future supplies ahead of a Martian landing), although time will only tell if humanity sends one of their own to visit the crimson world within the next half century.