how far can we shine a laser and detect it away from earth?
441999
That depends on the intensity of the laser, and whether you are aiming it from the earth surface or from a satellite outside the earth's atmosphere. Any beam, laser or flashlight, diverges from its source, and becomes lower in luminence with distance. A laser does not decrease by the inverse square, in the main advantage.
1038017
The galaxy Abell 1835 IR1916 is reported to be 13,230 million light-years from us.\n\nRed shift is the main method of estimating distance from us. We can also measure distance by the apparent luminosity of certain objects, such as variable stars and supernovas.\n\nAs our telescopes look further and further away, we are also looking back in time. So what we see past the furthest galaxies would be gas, and beyond that is the cosmic background radiation from the time the universe cooled to the point where it ceased being a plasma.
333277
We've been measureing this quantity for a number of years, and we are getting better results all the time.  The best news is that the different techniques we have been using all agree that the distance is about 26,000 light years.
1055664
You can do it with a laser a small circular obstacle (1cm diametre) and some lens. You built a telescope like picture to have 2cm diameter beam  you put the obstacle in front and you regard at 20 cm from the target
183503
For instance, astronauts have attached a mirror to a rock on the moon; scientists on earth can aim a laser at this mirror and measure the travel time of the laser pulse--about two and a half seconds for the round trip, which gives about 3.00E8 m/s for the speed of light.\n\nIts speed can also be derived from Maxwell's equations for the speed of propagation of electromagnetic fields in vacuum.
555650
I suppose it would be possible in theory. You would need an insanely bright source to project anything easily visible from Earth though. Why would you even want to do that?
988345
Almost any light can be seen from space. It just depends on what kind of telescope you have.\n-Brandon Everett Spurgeon
208385
There is significant research being done in imaging through objects like bricks, etc. However, much more research needs to be done. And the technology is still very far away to image such tings from space. \nSo NO.\n\nHopefully the technology would be used to image into the ground and used for mine detection in many parts of the world.
928062
Well you can use spectroscopy to find out the composition of distant objects in space.  IE if a star emits light near (usually a slight red shift from distant objects) the emission lines of helium or mercury you could conclude that those elements are present.\n\nMike
505155
I think everyone else has answered this pretty clearly.  NASA looked into constructing 'solar sail ships' for space travel.  A solar powered laser placed near the sun would generate a focussed beam of mono-phasic laser light that would be directed onto an extremely light ship which maximised surface area to mass/volume by use of a special sail.  This would provide a small forward acceleration away from the laser.\n\nHowever, on Earth.. as indicated.. its a bit impracticle with present power source technologies.  You may want to think about approaching to problem of fusion power and then minimizing the technology for youur application ( a long time field of research.. not an overnight job!!).\n\nGood luck!
871918
only in space where there is no air\n\nof  course there no clouds either but electrical spark can still be produced artificially\n\nedit: "a mile away for every second counted: -- make this about 4-5 seconds; the sound speed is about 300m/s
1040502
So much misinformation in the answers here. Your laser pointer will hit the moon, but because the power of the laser is small, less than 1 watt, you can't detect the reflection. With a 100+ watt laser beam, striking the reflectors that were left on the moon's surface, and using a telescope, the return can be detected and even measured.
1079162
Taking it simply, yes, this experiment would work.\n\nIt would need to travel much faster than the speed of light, or travel for a long time to get out beyond the light you are hoping to turn around and capture.  In that case, it would need to be a VERY powerfull telescope to pick out and see distinct images from the earths surface.  (even telescopes in orbit have a tough time making out small objects.)\n\nBut the experiment would work.  It takes time for light to travel.  We see the stars as they existed thousands of years ago.
857141
Apparent magnitude -- 1.3\nDistance -- 35 light years
715593
yes in theory a small laser can be attached to nano machines to cut through matter, but we dont have the ability to create them yet.\n\nHowever, this is  not the best solution to destroying a meter, we could simply nuke it, or divert its dirrection if its in earths path
131984
it will be pretty close unless you have sophisticated equipment capable of measuring about 93,000,000 miles accurately
462356
It probably requires a mass spec technique.  Infrared might work.  Your detection level will be the problem.