Author Topic: lazer ranging??  (Read 9930 times)

Offline mikejohnson

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lazer ranging??
« on: January 28, 2013, 08:54:35 PM »
Is this something that a amateur space geek can do?

Offline cjameshuff

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Re: lazer ranging??
« Reply #1 on: January 28, 2013, 10:10:07 PM »
Not alone. It takes a reasonably large (multiple meters aperture) telescope and some laser and photon counting equipment that, while not terribly exotic, isn't cheap or trivial to put together into a working system. A group of well equipped and well funded amateurs might do it though.

This page has lots of details:
http://physics.ucsd.edu/~tmurphy/apollo/apparatus.html

Offline Echnaton

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Re: lazer ranging??
« Reply #2 on: January 28, 2013, 10:59:41 PM »
I am not sure that it would be the best way for amateurs to contribute to science, but it would be cool.
The sun shone, having no alternative, on the nothing new. —Samuel Beckett

Offline Nowhere Man

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Re: lazer ranging??
« Reply #3 on: January 28, 2013, 11:39:46 PM »
And by the way, it's laser with an S, not a Z.  Originally the acronym for Light Amplification by Stimulated Emission of Radiation.

Fred
Hey, you!  "It's" with an apostrophe means "it is" or "it has."  "Its" without an apostrophe means "belongs to it."

"For shame, gentlemen, pack your evidence a little better against another time."
-- John Dryden, "The Vindication of The Duke of Guise" 1684

Offline ka9q

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Re: lazer ranging??
« Reply #4 on: January 29, 2013, 04:29:06 AM »
If you just want to bounce electromagnetic signals off the moon, and you don't particularly care about the wavelength, try ham radio moonbounce (EME).

New modulation methods have made it possible with much smaller antennas and lower power amplifiers. It's gotten rather popular.

There's not much original science in EME; it's more like climbing Mt. Everest because it's there, not because you'd be the first. But it has occurred to me that it might now be within the realm of possibility for suitably motivated radio amateurs to do some coherent radar imaging of the moon. That would be pretty cool, even if it has already been done for decades by large radio telescopes.



« Last Edit: January 29, 2013, 04:32:07 AM by ka9q »

Offline cjameshuff

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Re: lazer ranging??
« Reply #5 on: January 29, 2013, 10:03:40 AM »
It might be possible to adjust their approach somewhat and detect the reflectors with a group of smaller telescopes (at the high end of the amateur range). Their detection technique involves splitting the light up among multiple detectors anyway (allowing them to time multiple photons individually), so this might actually be a way of increasing performance.

Also, their laser is fairly low powered, just a couple watts, but designed to produce very consistent 100 picosecond pulses. You should be able to get by with longer pulses with a much higher power laser, especially if you just want to detect the reflectors.

It'd still be very expensive and of doubtful scientific value, though.

Offline Bob B.

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Re: lazer ranging??
« Reply #6 on: January 29, 2013, 12:39:56 PM »
Is this something that a amateur space geek can do?

Already been done  :)


Offline mikejohnson

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Re: lazer ranging??
« Reply #7 on: January 29, 2013, 08:31:32 PM »
haha thats funny bob, thats what made me think of this.