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The Lick Observatory laser utilized on the night of the Apollo 11
moonwalk emitted 8 Joules per pulse and the spot diameter was "about two
miles."

http://science.sciencemag.org/content/166/3901/99
http://www.ucolick.org/news/2009/apollo11.pdf

Let us assume spot diameter = 3000 m. Then area = 7.1e6 square meters,
and power density = 1.1e-6 J/m2, or 1.1e-10 J/cm2.

An article in Wikipedia includes a graph "Maximum permissible exposure
(MPE) at the cornea for a collimated laser beam according to IEC 60825,
as energy density versus exposure time for various wavelengths."

https://en.wikipedia.org/wiki/Laser_safety

For pulses 1 ns to 10 us (the Lick laser was in that range), the MPE is
6e-7 J/cm2, about 6000 times greater than the figure I calculated above.
Perhaps that's applicable to repetitive pulses if the duty cycle is very
small, like those transmitted from Lick. I'm not sure, though.

According the PDF above, it didn't matter since the beam was aimed at
the wrong part of the Moon! On the phone call between the Lick and
Houston, "fifteen" arc seconds in the landing site latitude was copied
as "fifty" at Lick.

But unless I miscalculate, that would not be a serious error. On the
Moon, 35 seconds of latitude is about .3 km. If the spot radius is 1.5
km, the landing site should still be in the beam — ?

   

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