Mars mission faces a hurdle: Astronauts may arrive paralyzed The Globe and Mail

With the recent success of the rover Spirit, and the anticipated landing of Opportunity later this month, a manned mission to Mars is the talk of the planet. However, according to new McGill University research, stress caused to the human body by the weightlessness encountered during space missions may present a formidable obstacle to U.S. plans to establish a colony on the moon and launch a manned mission to Mars by 2030.