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ArcticMyst Security by Avery

This Is What a Laser From the Moon Looks Like (Photo)

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I don't know when I'll have the chance to do this but I will report back if I have any luck. I wish I had a camera for my scope, that could be a cool picture.
 





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Yeah I imagine it would take a bit of luck to be able to hit the mirrors, ill have to see if I can find some information of where the mirrors are located on the moon. That would be a awesome sight tho to see a blue reflection glaring back at me.

I don't know when I'll have the chance to do this but I will report back if I have any luck. I wish I had a camera for my scope, that could be a cool picture.

It has been done before.
Subject: Visual EME !

(I used to be able to sparkle off the new moon with my YAG at full power and full convergence. It takes some doing but you can see the sparkle from the sea of tranquillity with the naked eye off the corner cube reflector, aka: retroreflector left there in 1969 by the astronauts....)

: Interesting.What did you collimate the beam with?: What was the lasers' power.

Galilean beam expander. 80mm on the output objective (high precision achromat, not planoconvex) and a 5mm doubleconcave on the input. All lenses were AR coated and cooled (otherwise they'd ablate/vaporize). Divergence was very low with this beam expander. :)

Lasers power (input) was greater than 10 joules pulse, at a 15Hz rep rate, 532nm wavelength. Twinkle was seen with a Celestron telescope and my eyeball. Not very scientific but fun. If the moon is new, you can see the twinkle of green with the naked eye, full moon requires a telescope to isolate the scant few photons that make it all the way back.

(I use this YAG for advertising new Lasertag gamesites. It runs from Des Moines Iowa all the time, and pilots tell me the beam is visible as far way as Denver from Des Moines, and Chicago from Des Moines. These are the only reports I've received, from the regular routes. I've only gotten friendly with the local pilots, never get to know the ones when I'm running remote. It's been in Berkeley, Sacramento, Ft. Wayne, Evansville, and will be running next week in Cancun Mexico.

Now before anyone gets upset, I have a CDRH variance to operate this yag in an outdoor environment WITHOUT a beam block or termination point, and have FAA authorization and air clearance as well. 100% legal and by the book!

Please note I turn the power way down for beam shows, the power level to shoot the moon was a special case and I had TWO plane spotters for safety. The power output is 0.9725mw cm^2 at 750 feet which translates into a fiber launch power of about 30 watts, not over 35 watts, so it's safe..........)

-=<EOF>=-http://www.k3pgp.org/viseme.htm
 

IsaacT

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I imagine you would need damn good divergence on your 3W 532 to get anything discernible back but definitely hit it with your best shot.

Edit: Fire away.
 
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You might consider running your 3W laser beam through another large telescope to recollimate/increase the beam diameter/decrease the divergence so as to produce the smallest "spot" possible at the Moon reflector.:beer:

T.
 

ru124t

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Hmmm I wonder if a g2 lens might make that dot a little more impressive looking coming from the moon ?
 

IsaacT

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On a 532nm laser you shouldn't be using a G lens. A long focal length lens with a larger diameter of about .5" would be preferred.
 

ru124t

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Dude, the thread was this is what a laser looks like coming from the moon. The dot was a fuzzy picture. The joke was maybe they should use a g2 lens to make a nicer dot! lol see first thread lmao
 
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Dude, the thread was this is what a laser looks like coming from the moon. The dot was a fuzzy picture. The joke was maybe they should use a g2 lens to make a nicer dot! lol see first thread lmao
I know, but to improve the beam requires low divergence which a g2 lens with a focal length of 6.3mm would not have. Do you understand why the setup used to point at the reflectors would also work if pointed at the Earth?
 
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I've been to one of the installations in Hawaii. I saw it in action back in 1992. It was a small compound on the northern island of Kauai. They wouldn't let us inside however the intense green beam was clearly visible shooting into the sky. Especially with the low light conditions there.
 
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Dude, the thread was this is what a laser looks like coming from the moon. The dot was a fuzzy picture. The joke was maybe they should use a g2 lens to make a nicer dot! lol see first thread lmao

A G2 lens makes the dot crappy just look up dot sizes 3 element vs G-2 :thinking:

All it does is pass more light.
 
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Because regardless of source origin the medium travelled through and distance is mathematically equivalent?
 




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