Farthest your laser has gone for sure?

[Scotty 757]

I'd think it would take considerably less than 18W to clear the atmosphere.. I read a paper that talked about a HeNe (probably large-frame) that was detected from a Space Shuttle.. can't cite the source, though.

Wow that's amazing. I guess I would think something would happen but probally not. What would happen to a laser beam in space?

 

[sandidgepatrick]

yahh i cant wait to get my x10 expander....i have lots of wide open land with a mountain about 10 miles away that im going to shoot from...its at 4000ft. diff. going to do some long and short dist. tests....

 

[StardustSprinkles]

^no light pollution in space!

 

[photonaholic]

Photonaholic, if that's where you live in your profile pic, it looks beautiful.

Thank you, that picture was taken on my race track behind my house.

Also...

Now back to our topic at hand....

 

[Scotty 757]

^Damn. I want that land. That's awesome man.

 

[Scotty 757]

That would be intresting BobH. I want to touch the moon.

 

[photonaholic]

What would happen to a laser beam in space?

Space is not 100 percent free of dust and particles to diffuse the beam, and divergence would still be the same.

However, in an ideal location (complete darkness, no debris) I'm confident that one could detect the beam from a far greater distance.

The atmosphere of our planet does filter and diffuse light, It performs that very function to the suns rays as the radiate towards earth. (without our atmosphere the UV would burn us up quickly)

 

[Laser_Ben]

Well, doing out the math, my Millennia will cause blindness at 11.4km....

 

[Scotty 757]

That's pretty far. You could really do some damage. What's all those boxes to the left?

 

[Laser_Ben]

Oh, it's hardwood flooring for the other side of the house.

 

[Eudaimonium]

Laser_Ben, have you tried shining that thing on the moon?
Since I can still see it, I guess not.

 

[john_lawson]

I had my daughter drive to this large factory about 7 miles away i shinned my RPL 375 at the tall 175 foot smokestack she said she say it pretty well she said it was huge though like 10 foot wide

 

[Greenmechanic]

I read somewhere on here about a guy shining his high mW 532nm, and spotting it 35 miles away. This was in the mountains although. Mountain top to mountain top.
Cold, very dry air.

Found it. Also talk of of a hobbyist's laser being visible from the ISS and the moon.
http://laserpointerforums.com/f45/35-mile-laser-shoot-40481.html
I don't know for sure if you could see it from the ISS, but it seems possible. (they did the math formula's that said it's possible)
In my experience, about 3 miles is the farthest I've seen the dot.
Sitting up on the peak of the roof, shining it at a known 3 mile distant tower.

 

[rangedunits]

i tested 2km, was able to see the dot with my eyes.

Laser used: x-75

 

[ninja_tux]

Space is not 100 percent free of dust and particles to diffuse the beam, and divergence would still be the same.

However, in an ideal location (complete darkness, no debris) I'm confident that one could detect the beam from a far greater distance.

The atmosphere of our planet does filter and diffuse light, It performs that very function to the suns rays as the radiate towards earth. (without our atmosphere the UV would burn us up quickly)

Well space is actually a pretty complete vacuum, and unless you were to shine it though an area with fine, densely packed, debris, you wouldn't see the beam since a laser's beam is just the photons reflecting off of particles they encounter. The DOT however would be able to forever technically, assuming it doesn't hit anything. This is because photons are massless and travel at the speed of light, so short of hitting something or encountering a black hole, there's nothing to slow them down in outer space.

 

[Solaryellow]

And the beam width is how many miles wide on the moon?

I tried to calculate that once using the basic divergance of an average laser,
1.5mRad 240,000 miles.

or a spot about 385 miles wide..

My Green diverges to about 5 feet at 1 google map mile...

Uses a building and a friend with a tape and cell phone to tell me to hold still..


Speaking of Moon, I held a piece of Moon rock.

Well almost, it was in a protected case.