Day of triffids scenario aside, no you won't lose your sight from a 2.5W laser pointing downwards from 260 miles up. The power level is too small. People think

Day of triffids scenario aside, no you won't lose your sight from a 2.5W laser pointing downwards from 260 miles up. The power level is too small. People think that lasers produce a parallel beam. They don't - they are diffraction limited by the width of the beam. The narrower the beam, the more it spreads out. For example, a 1cm wide beam produced by a perfect laser would spread out to around 20m wide when it hits the ground from 260 miles away. That's assuming visible green light - if it's infra-red (or even just red) then the spread will be wider.