Can anyone tell me how dangerous it would have been for Apollo astronauts to look directly at the sun with their visor up? In this video clip an astronaut is advised to lower his visor "out here in the sun".

http://www.hq.nasa.gov/office/pao/Hi...7v_1650053.mov

It is pretty dangerous to look directly into the Sun right here on Earth; you don't have to be on the Moon to blind yourself.

It would have been dangerous to look at the sun with the visor down.

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Living on Earth may be expensive, but it includes an annual free trip around the Sun.

I think the visor is handy when you accidently look in the direction of the sun: you don't get eye damage from the very first moment you do it, you get some warning time. But I wouldn't look directly into the sun with it 8)

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To the regular visitor of internet bulletin boards it is clear that it's an excellent idea your parents get to choose your real name.

I've done this calculation before.

The Earth's atmosphere absorbs or reflects about 30-40% on the incoming solar energy. Varies with were to live on the planet.

Also, the Earth's ozone layer absorbs the most dangerous ultraviolet radiation. I imagine a full dose of UV could cause some pretty serious burns if it were not blocked by the visor. I've always assumed the visor was mainly for UV protection.

The bubble helmet is made out of Lexan, which is pretty opaque to UV.

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"Flying in space is risky business, but just staying on this planet is risky business too." - John Young, astronaut

Thanks for the replies everyone. Pretty much what I thought - good to have it confirmed/clarified.