For a manned mission to Mars in 2020

Using NASA's microgravity facilities, the duo hope to develop preventive medicines that the astronauts can take with them to guard against bone-mass loss caused by long-term space exposure.
One of the main limitations to long space travel is space radiation, and we plan to enhance the natural killer cells in astronauts to tackle the damages.

Wired News: Careful With That Petri Dish
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