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ArcticMyst Security by Avery

Lasers in space

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Yeah, I know none of you can provide pictures of this.. but...

what would it be like to turn on a laser in space? How would the laser work? Or like.. would it go a farther distance? How would the photons behave differently (if at all)? :?

Also, I have another question: in comparison to the speed of light, how fast do laser photons travel? Same speed?

Would be friggin cool to experiment with lasers in space.
 





IsaacT

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Lasers are light so they will travel at the speed of light
 
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Yeah, I know none of you can provide pictures of this.. but...

what would it be like to turn on a laser in space? How would the laser work? Or like.. would it go a farther distance? How would the photons behave differently (if at all)? :?

Also, I have another question: in comparison to the speed of light, how fast do laser photons travel? Same speed?

Would be friggin cool to experiment with lasers in space.

I always facepalm when someone asks this. Lasers don't "go" a certain distance. It's understandable why someone might ask the question, but you should understand that the light will travel forever until it is blocked by an object.
 
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Well you wouldn't see a beam, but light can actually propagate better in a vaccum where there is no medium.

And you can always count on those longer wavelengths of light to travel just a little bit faster than your blues and violets.
 
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I always facepalm when someone asks this. Lasers don't "go" a certain distance. It's understandable why someone might ask the question, but you should understand that the light will travel forever until it is blocked by an object.
If that is the case, then they could use lasers as a form of long-distance communication ... or at least one way of doing it. :p

Kind of like fiber and infrared connections. They could stream HD videos of Mars like this. :eek:
 

IsaacT

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I know it isn't long distance, but you can transmit your voice via laser to a speaker a ways away very easily and fairly cheaply.
 
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If that is the case, then they could use lasers as a form of long-distance communication ... or at least one way of doing it. :p

Kind of like fiber and infrared connections. They could stream HD videos of Mars like this. :eek:

Well, sort of. Scientists often bounce lasers off the moon and record the time it takes for the photons to travel back. However, only a very, very few number of photon actually make it back to the scientists on Earth. Even then it's hard to distinguish them from other photons that didn't come from the laser.
 
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lay of the getting toasted, and wake up in your basic science classes.:whistle:
 
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Well, sort of. Scientists often bounce lasers off the moon and record the time it takes for the photons to travel back. However, only a very, very few number of photon actually make it back to the scientists on Earth. Even then it's hard to distinguish them from other photons that didn't come from the laser.
But what if you had a satellite that would transmit/receive data between the space craft, and then the right technology for back-to-ground-on-Earth transmission.

Space craft would only have to be able to see the satellite from Mars, and as long as the lasers on both can be seen by each other (satellite <-> spacecraft), it should make a somewhat alright connection (except for when debris floats through or other planets/moons are in the way).
 
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But what if you had a satellite that would transmit/receive data between the space craft, and then the right technology for back-to-ground-on-Earth transmission.

Space craft would only have to be able to see the satellite from Mars, and as long as the lasers on both can be seen by each other (satellite <-> spacecraft), it should make a somewhat alright connection (except for when debris floats through or other planets/moons are in the way).

But why use a laser when there are other, better forms of electromagnetic communication?
 
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Radio waves travel at the speed of light, just like.. well.. light does. :p There is no speed improvement.. at least due to the medium that's carrying the information, of lasers over RF. The only benefit lasers would have in communication, would be the ability to send information to specific areas, and not just the 'general direction' of the receiver.. Though even this is really only practical over relatively short distances, considering it's not possible to achieve a perfectly nondivergent beam.

The only true advantage lasers would have over longer wavelengths is that the smaller the wavelength, the faster it can be modulated, which means the more data that can be transferred.
 
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HotUSA

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If you pointed your simple torch to the sky. the light will travel forever. . . .
until it hits something out there.
 

IsaacT

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remember that there are molecules in the air. If the atmosphere was a vacuum with no molecules then tht is one thing. But with all of the particles floating around, light gets filtered out by a certain point. Thats why it won't just "go on forever".
 
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I believe that TV transmission satellites use wavelength on the order of a dozen centimeters of so, which qualify as microwaves. Radio waves are a little too un-directional sometimes. But that again depends of the wavelength. AM broadcast towers can be made very directional- you can pretty much aim them to anywhere in the world.

So as far as communication goes, I think microwaves are best as they don't need a perfect line of sight connection, and they don't get stretched out too much when they pass through dense gases... such as water vapor.
 




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