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FrozenGate by Avery

Distance Experiments






Can you really measure the true distance? I mean it depends on a lot of things, the main being the particles in the air. Though this makes me wonder, if you were to have light, or more specifically, electromagnetic waves, travel though space with no atmosphere, would space alone convert the waves into something/cancel them out (basically change electromagnetic waves like particles with mass do to allow us to see "light", or in other words, conversion), or would it go on infinitely, until something does show up, like planet for example, converts it? So basically, (though not true), if in theory, there was no mass in space (like planets/asteroids, etc), and space was infinitely long, would it go on infinitely?

This has always wondered me. :O

P.S. I have edited my post several times as I can't seem to explain my question too well.... I'm not very good at explaining, it seems... Hopefully it is interpreted the way I mean it too be.

Thanks!
-Moptsp
 
Last edited:
A while ago, another LPF member used a beam expander to make a visible dot on Mt. Jefferson 35 miles away. Counting the reflection, that is a total of 70 miles. What is even more impressive is that just the dot was visible at a distance of 35 miles! If someone looked towards the source of the beam, it would be visible at a much greater distance.

Here is the thread, by the way: http://laserpointerforums.com/f45/35-mile-laser-shoot-40481.html
 
Moptsp said:
Can you really measure the true distance? I mean it depends on a lot of things, the main being the particles in the air. Though this makes me wonder, if you were to have light, or more specifically, electromagnetic waves, travel though space with no atmosphere, would space alone convert the waves into something/cancel them out (basically change electromagnetic waves like particles with mass do to allow us to see "light", or in other words, conversion), or would it go on infinitely, until something does show up, like planet for example, converts it? So basically, (though not true), if in theory, there was no mass in space (like planets/asteroids, etc), and space was infinitely long, would it go on infinitely?

This has always wondered me. :O

P.S. I have edited my post several times as I can't seem to explain my question too well.... I'm not very good at explaining, it seems... Hopefully it is interpreted the way I mean it too be.

Thanks!
-Moptsp
Click to expand...


I think I understand you.
Yes, light (any electromagnetic radiation) will travel on for an infinite distance until it is completely attenuated.
In space, the beam will be invisible because there is nothing to reflect the beam. The spot will still be visible, however, if there is an object to point it at. Photons can be observed, but cannot be "seen." In order to see an object, it must reflect visible light. Photons are light, and so do not reflect light.
The little calculation I provided was just to get an estimate of what X laser will look like at X distance. It is pretty rough, and doesn't take into account distortion from turbulence or inconsistencies in the atmosphere but it will get an accurate enough result for what we're doing.

ixfd64:
Yeah I remember reading that. It's interesting that with only 3X expansion the dot can be seen. I think that if anything, the light would be only just visible.
 
In 6th grade, I was on a school trip to this camp where some other schools went, and I met a kid who started talking to me about his dad working for SWAT. He told me he got to use all kinds of gear, and that he had a kick ass green laser on his gun. I asked what kind it was, and he told me a WL spyder (I'm not sure what version, but it was the most powerful at the time) and that he went to a training exercise in new mexico, and they shined the laser 20 miles on to a cliff face and the guys at the receiving end could see it. I didn't ask about divergence or anything, but I thought that was pretty cool.
 
RA_pierce said:
I think I understand you.
Yes, light (any electromagnetic radiation) will travel on for an infinite distance until it is completely attenuated.
In space, the beam will be invisible because there is nothing to reflect the beam. The spot will still be visible, however, if there is an object to point it at. Photons can be observed, but cannot be "seen." In order to see an object, it must reflect visible light. Photons are light, and so do not reflect light.
The little calculation I provided was just to get an estimate of what X laser will look like at X distance. It is pretty rough, and doesn't take into account distortion from turbulence or inconsistencies in the atmosphere but it will get an accurate enough result for what we're doing.

ixfd64:
Yeah I remember reading that. It's interesting that with only 3X expansion the dot can be seen. I think that if anything, the light would be only just visible.
Click to expand...

Yep. You get me completely! Thanks alot. :)

-Moptsp
 
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