Mars Mission, nine months out, nine months back.

And, Bob, there's been on and off research

that I've read over the years.

You've read all of it, about the changes

to a body and a brain and eyesight in an Earth orbit.

And that raises always the question about whether mankind is for long voyages.

In Earth orbit, at least there's nominal connection to Earth

and nominal connection to gravity, but nine months to Mars. What do we know

about what that would do to a body? It's hard to say right now, John.

The issue is weightlessness and radiation.

Weightlessness causes a whole series of issues, and there's real questions whether or not anyone could

function after a year after six months in space

and get the got to Mars.

Your muscles get weak, you would land on Mars and that weak gravity would be very big problem

for you. There's other issues having to do with vision and

and cardiovascular system. A most recent research looking at humans and

animals and simulations as well as modeling,

so this uncertainty here, strongly suggests

that once a mission is into planetary and out beyond the Earth's

magnetic field the cosmic rays that hit randomly would cause significant damage to the kidneys so much so that

those kidneys after a two and a half year mission would be permanently damaged and not be able to function. 2.5

1⁄2 here mission would be permanently damaged and not be able to function.

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