DiscoveryNews: Lunar Mirror Mystery Solved

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bystander
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DiscoveryNews: Lunar Mirror Mystery Solved

Post by bystander » Sun Mar 14, 2010 8:40 pm

Lunar Mirror Mystery Solved
Discovery News - 2010 March 14
  • Reflectors were placed on the moon during Apollo missions.
  • During a full moon, their reflectivity drops by a factor of 10.
  • New research proposes that dust on the reflectors heats up during a full moon, distorting their shape.
The Mysterious Degradation of the Apollo Reflector Arrays
Technology Review: physics arXiv blog - 2010 March 05
The efficiency of the Apollo reflector arrays drops by a factor of ten during a full moon. Now a new analysis may explain why.
Long-term degradation of optical devices on the moon
arXiv:1003.0713v1 [astro-ph.EP] 2010 March 03
Forty years ago, Apollo astronauts placed the first of several retroreflector arrays on the lunar surface. Their continued usefulness for laser-ranging might suggest that the lunar environment does not damage optical devices. However, new laser ranging data reveal that the efficiency of the three Apollo reflector arrays is now diminished by a factor of ten at all lunar phases and by an additional factor of ten when the lunar phase is near full moon. These deficits did not exist in the earliest years of lunar ranging, indicating that the lunar environment damages optical equipment on the timescale of decades. Dust or abrasion on the front faces of the corner-cube prisms may be responsible, reducing their reflectivity and degrading their thermal performance when exposed to face-on sunlight at full moon. These mechanisms can be tested using laboratory simulations and must be understood before designing equipment destined for the moon.
Given neufer's previous involvement, I thought he might be interested.

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neufer
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Re: DiscoveryNews: Lunar Mirror Mystery Solved

Post by neufer » Sun Mar 14, 2010 9:45 pm

bystander wrote: Given neufer's previous involvement, I thought he might be interested.
So nice of you to remember...thanks, bystander.

I too have degraded somewhat over the years.
Art Neuendorffer

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rstevenson
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Re: DiscoveryNews: Lunar Mirror Mystery Solved

Post by rstevenson » Sun Mar 14, 2010 10:27 pm

neufer wrote:I too have degraded somewhat over the years.
Ah, but we bask in your reflected glory nonetheless. :wink:

Rob

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neufer
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Re: DiscoveryNews: Lunar Mirror Mystery Solved

Post by neufer » Sun Mar 14, 2010 11:15 pm

rstevenson wrote:
neufer wrote:I too have degraded somewhat over the years.
Ah, but we bask in your reflected glory nonetheless. :wink:
REFLECTED glory....hmmmm. :?
Art Neuendorffer