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Is the LASER beam visible in space?

Benur

Benur

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This morning I had a doubt about lasers.
If the laser beam is seen thanks to particles in the air, then, is the laser beam seen in outer space?
:thanks:
 





Well laser beams are seen by astronauts in space in the space station coming up from earth, as far as outer space goes i assume there is space particles all around in outer space. I haven't done a Google for the answer but i would presume this ro be correct you can see laser beams in outer space.
 
No since space is (supposedly) a vacuum, you wouldn't be able to see a laser BEAM. You will see the laser if the laser is aimed at your eye from space, but even if the collimation was .00000000000001mRad you wouldn't be able to see the laser BEAM in space. Now, since we all of this junk and crap floating around the Earth you might be able to see a little bit of the beam through the urine droplets or something :p
 
Hwangs post was pretty much spot on. The orbits where most satellites and the space station are have some atmosphere. Outer space is a vacuum so no atmosphere, there will be particles floating around (interstellar dust etc), but much less than back in our atmosphere to scatter the light. Scattering is however dependent on wavelength and particle size.:beer:
 
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A beam could be visible in space due to the rayleigh scattering off:
1) interstellar dust (as mentioned before)
2) interstellar gasses
3) recent studies have seemed to find that rayleigh scattering can occur off free electrons in space (I'll try to find the study if I can)
 
Yes, the beam is visable in space i believe, if there is something to re-direct the photons away from the main beam. N04H99 summed it up
 
hwang21 said:
Now, since we all of this junk and crap floating around the Earth you might be able to see a little bit of the beam through the urine droplets or something :p
Click to expand...

This is a valid point really, when we are talking about space as in earth orbit.

Normally the -beam- would not be visible at all since there is nothing in space to scatter it, but there is plenty of 'crap' in low orbit that could actually scatter/reflect the beam. It would not be consistent like the scatter from the atmosphere, but more like what you see when you aim a laser through falling snow: incidental reflections, though much less frequent in space compared to during snowfall.
 
But I'm talking about outer space, not about space as in earth orbit. Like the laser of the Death Star in Star Wars.
 
In that case, no you would not be able to see any of the laser beam, assuming a complete vacuum. Due to interstellar dust and such you may be able to pick up the faintest trail but for the most part, you cannot see the beam at all
 
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Ironically enough there is no law of physics that makes the death star impossible :) There is no upper limit on the amount of energy you can pump onto a lasing material :)

Practicalities and heat are a different matter :)

cheers

Dave
 
I'm pretty sure particles in the air just emphasize the beams presence, in a clean, particle less environment, the beam would be visible. I would think... Correct me if I'm wrong
 
KRNAZNBOY said:
I'm pretty sure particles in the air just emphasize the beams presence, in a clean, particle less environment, the beam would be visible. I would think... Correct me if I'm wrong
Click to expand...

Depends if you're including subatomic particles (free electrons and such) as particles.

Your beam will always exist, even if not visible. It will only be visible by reflections (when the light hits a particle whose diameter is larger than the light's wavelength) or by scattering (which occurs when the light encounters particles smaller than its wavelength).
 
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