What would happen if I put my arm out in space without a space suit?

On Wed, 31 Mar 1999 you wrote:

> Answer this question if you can.What would happen,physically if I where on a
> space ship near the moon,and put my bare arm out into void space,with out a
> space suit?Sorry for asking so many questions but there are things I have to
> know.

The reduction of pressure caused by sticking your arm out into space
would cause several effects. First, all the gases dissolved in your blood
(oxygen and nitrogen) would bubble out (a similar thing, called the
"bends", happens to divers who rise out of high-pressure water too
quickly). Your arm would swell somewhat due to the reduction in pressure
- I'm not certain if it would swell enough to burst or not. Finally, the
intense ultraviolet radiation of the sun would give you a severe sunburn
in a matte of seconds.

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