[Laser] 3rd attempt to post.

[Charles Pooley]

Some kind of bug I don't understand.  I've cut/pasted reply and am trying as an original email, not a reply:
   
   The 1st attempt to post bounced--it said it was an html.  I've removed 
Andrew's address and try again:

"Andrew T. Flowers, K0SM"  wrote:
   
  Putting a laser on the surface of the moon and pointing back at a 
target 
on earth is no trivial task. Many people forget that although the moon 
generally has one side facing earth, it wobbles around 
considerably--this is what causes libration fading for those of you who 
are familiar with EME. If you wanted to put a laser up there and point 
it back toward earth you would have to compensate for this complex 
wobbling.

Andy K0SM/2
-------------------------------
  My reply:
  
  As part of the Microlaunchers effort, I will be designing, posting on 
my site some example calculations.  It will actually be fairly easy 
(once a device has been landed onto the lunar surface, or course).  A 
camera can be kept trained on the Earth, and with a periodically 
updated 
schedule, the spot on the Earth where the downlink telescope is can be 
maintained.  The lunar surface is quiet, stable so the slew rate of the 
aiming device can be very low.
   
  As with space to ground imaging, there are no turbulance effects for 
almost all the signal path.  With the assumed ability to count photons 
by PMT or Geiger mode APD, a small telescope is going to be ok.
   
  This is going to be easy after the landings can be done.  The 
launcher is everything.
   
  Charles Pooley     www.microlaunchers.com