What?
When you see light of course it is beams of moving light.
All light is moving light waves, the colour you see depends on what colours of the specrum are reflected, and which are absorbed
It is impossible to send a laser into space, and for them to see it.
To get to the end of the known universe, actually lets use our galaxy, the milky way.
It would take a very very very long time. not just a matter of year, but qa matter of decades. And there is no possible way of them seeing somethign as small as a beam of light.
If there was an end to space, the light would just stop. It couldn't pass through it, because it is hitting something.
It could have bounced off of thing (dust particles, other planets, etc) but then it wouldn't be travelling in a straight line, which is the whole thing behind the experiment.
Light travels in straight line - if it stops going, then there is an end
It hitting things on the way make it go off in different directions, which screws it up.
Either way, there are no telescopes powerful enough to see how far the beam would go, because it is such a small beam.
For all we know, we may be the edge of the universe(s) *in saying that, I don't mean the known universe, I mean the entire enity of space* And the centre is way the fuck in the other direction then people are looking.