Comment Re:chinese anti-satellite lasers (Score 4, Informative) 253
"A 1um laser fired out of a 1m aperture spreads to an 800m circle at an altitude of 800km"
You're off by a factor 1000. The divergence is about 1e-6 rad, which makes 0.8 m diameter at 800 km.
Now another issue is that satellites tend to be wrapped in gold-coated foil, which will reflect 99% of the light at 1 micrometer. It would be difficult to overheat the body of the satellite, although the solar panels might be damaged more easily.