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ArcticMyst Security by Avery

You can't see laser beams in space.

Alaskan

Alaskan

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I've seen a photo of a 1 watt blue laser as viewed from the ISS, nice blue dot which did well for being so low power compared to the rest of the lights in the city nearby. I will have to get my wife to point my laser straight up some night while I am viewing from a couple of miles away to know if I can see it. Maybe I will take a drive up the mountain side and have her sweep towards me and above to see if the beam is visible a few miles away.

Edit:

ISS-flash-full_zps9d18cb18.jpg


From: http://www.dvice.com/archives/2012/03/texas_blasts_th.php
 
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Alaskan

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I edited my post with the same info about the same time you posted, I guess.

Edit again: Oh, yours is a video of the event, thanks!
 
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WriggleyTinn

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I live reasonably high up a hillside here and know most of my view.... a friend asked me to shine my 200mw green laser towards his house 3 mile away... and when I heard him say "Wow... the tree is twinkling with loads of green particles" I knew he could see it and was amazed myself.....
 
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WriggleyTinn

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Forgive me if I'm wrong but wouldn't a dot at 1.5 miles at a divergence of 1.5mrad be around 3.5 meters... or 2,3 meters @ 1mrad?.... still a good distance on a 20mW Mr Evil
 
Teej

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Are we diverging from the visibility of the beam in space, to the visibility of the dot?
 
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WriggleyTinn

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Indeed Teej, I believe we are.... One must apologise for being diverse in deviating from the course of the thread... Please consider my wrists slapped
:-D
 
The Lightning Stalker

The Lightning Stalker

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Here is just xactly what the fax is.

The only source of the video is some nobody
YouTube channel full of 'UFO vidoes'.

OPALS operates at 1550nm. The camera
wouldn't pick it up. No one would see it.
Furthermore, it is only a measly 2.5W. I
have used a 1500nm laser and can verify this.

One time I saw a red point of light shoot
across the sky. A few minutes later,
another red point of light, possibly even
the same one, shot across the sky again,
following the exact same path. I have no
proof and cannot be sure it was actually
there.
 
Blarg King

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Question: Would a laser have better divergence in space/vacuum since there would be no atmosphere?
 
Alaskan

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Humm... I wonder how much our atmosphere affects divergence compared to a vacuum or is it purely a function of the device? My guess is they are completely unrelated, yet, atmosphere does bend light to some degree, maybe negligible unless at an angle across the horizon..
 
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WriggleyTinn

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Am I getting something wrong here.... Isn't it the lens that is responsible for the divergence of the beam (collimating lenses).

Nice laser you have there Dr Evil, the RPL, some pretty good stats with it :-
"Beam divergence (full angle) <1.00 mrad typically <0.9 mrad (Lowest true divergence in the industry)"
 
W

WriggleyTinn

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OPALS operates at 1550nm. The camera wouldn't pick it up. No one would see it. Furthermore said:
Hmmnnn.... A camera will pick up 980nm light, you can try this yourself:-
Hold the led window of a standard tv remote to the lens of your phone camera and press a button and you will see it light up.
With this I question the fact a camera wouldn't pick up a high powered laser at 1500nm and would think a direct hit to a camera would cause total "white out".... IMHO.. but I may be proved wrong
Click to expand...
 
Pi R Squared

Pi R Squared

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The Lightning Stalker said:
Here is just xactly what the fax is.

The only source of the video is some nobody
YouTube channel full of 'UFO vidoes'.

OPALS operates at 1550nm. The camera
wouldn't pick it up. No one would see it.
Furthermore, it is only a measly 2.5W. I
have used a 1500nm laser and can verify this.

One time I saw a red point of light shoot
across the sky. A few minutes later,
another red point of light, possibly even
the same one, shot across the sky again,
following the exact same path. I have no
proof and cannot be sure it was actually
there.
Click to expand...

If you can't be sure it was actually there then you can't be sure you even saw it can you? It was probably just two meteors burning in. I know meteors are usually white light but there are red, orange, and green ones too, also slower moving green fireballs. The color is probably due to whatever it's made of. There is also man made space junk reentering from time to time too.

After viewing the video again it looks more like something in space is being illuminated by a laser from earth or from lower in the atmosphere, although that too seems unlikely to me.

Alan
 
starlight

starlight

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Laser Project said:
I've seen a photo of a 1 watt blue laser as viewed from the ISS, nice blue dot which did well for being so low power compared to the rest of the lights in the city nearby. I will have to get my wife to point my laser straight up some night while I am viewing from a couple of miles away to know if I can see it.
Click to expand...
I made a video about 5 years ago of myself shining a 75mW green laser at my brother who was just over 5 miles away.

 
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