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US Congress Funds Laser Weapons
An anonymous reader writes "The Washington Post reports that the US Congress is funding laser weapons for use in the near future. Low-power lasers called 'dazzlers' are already being used in Iraq to temporarily reduce a person's vision. High-power laser weapons would allow precision attacks that minimize civilian casualties. From the Post: 'The science board said tactical laser systems could be developed for broader use because they "enable precision ground attack to minimize collateral damage in urban conflicts." The report suggested, for example, that "future gunships could provide extended precision lethality and sensing." The board also proposed using lasers to protect against rockets, artillery, mortars and unmanned airborne vehicles by blasting them out of the sky. Last month, the Army awarded Boeing $36 million to continue development of a high-energy laser mounted on a truck that could hit overhead targets. But deployment is not expected until 2016, even if all goes well.'"
This should hardly be a surprise to anyone; the United States government already has functioning platforms. Just this month, the Boeing Company test fired a fully working prototype of its Advanced Tactical Laser (ATL), a C-130 with a high-energy chemical laser on a rotating turret mounted on the belly of the plane. I don't know if it was a full powered shot, but the press releases indicate that it successfully hit a ground target. Then there's the larger Airborne Laser (ABL), an even bigger laser mounted on a 747 used to shoot down ballistic missiles.
A mirror will reflect some percentage of light that hits it, and absorb the rest. A sufficiently high-power laser will mean that the absorbed percentage is high enough to melt or burn the mirror.
If you put a mirror in the sun on a hot day then the back of it will become warmer than the surrounding air, which acts as a demonstration of this. The density of energy from the sun is quite small in comparison, however. Most anti-laser designs involve rotating mirrors, so that the mirror only has to survive a small fraction of a second before being the laser starts hitting a different part.
If you shoot a mirror (or anything other than a perfect black body) with such a laser then there will be some reflection, which is roughly analogous to a ricochet from a bullet. How much energy is contained in this depends on the intensity of the beam, the reflectiveness of the mirror, and the shape of the object at the point where it's hit (if it's not flat then the energy will be the same, but it will be dispersed or focussed).
I am TheRaven on Soylent News
This is simply wrong. The peak of civilian killing was WWII, when entire cities were targeted because that's as accurate as the bombers could get. Not only did this culminate in the complete destruction of two Japanese cities, but the US had already killed far more civilians with firebombs than it managed to kill with nukes. And the Japanese were hardly in a position to complain after their own actions in Korea and China.
Now we have weapons that are precisely targeted. So much so we can use bombs filled with concrete to destroy AA installations parked in civilian neighborhoods without killing people in the house next door. That AA position would surely have been destroyed in earlier wars as well, and it would have been done with 2000 pound bombs dropped on the entire neighborhood, or, more recently, a more precisely targeted 500 pound bomb that destroyed the AA installation because it was accurate enough to hit the house next door. Which is worse, do you think?
The laser would give us the option to be very precise, to the point where we could destroy vehicle tracks on an advancing armored column without injuring the soldiers inside. Someday that will be SOP, where countries that inflict unnecessary losses on enemy soldiers will be roundly criticized.