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Re: Paint the Moon



Regarding Tom Sandin's further objection:

The moon is about 400 million meters away. The reflector array has a
size of the order of 1 meter. Even if the beam could be kept from
spreading, the person holding the pointer would have to keep it aimed
to
within about 1/(400 million) radian or about 1/(10 million) degree. I'm
a
bit shakier than that. Tom Sandin

If one goes to the http://www.paintthemoon.org/ web site (mentioned
by Larry C.) where the proposer of this project explains it, he does
not want people to aim their pointers at the Apollo corner
reflectors. Rather he just wants them aimed a little to the dark
side of the terminator during a 1st quarter phase close to the middle
of the moon's exposed disk. The target spot size diameter seems to be
about 10% of the moon's diameter. Since the Moon subtends about
1/2 deg, this means that the aiming needs to be accurate to within
about 1/20 deg (or 3 arc min).

David Bowman
David_Bowman@georgetowncollege.edu