The point is interesting. A CO2 laser at 10 microns can melt steel, which emits a whole lot of 0.5 micron photons. The problem with sunlight reflected off the

The point is interesting. A CO2 laser at 10 microns can melt steel, which emits a whole lot of 0.5 micron photons. The problem with sunlight reflected off the moon is that it's like having a very low transmittance ND filter in the optical path. There aren't a whole lot of photons entering the aperture, and as the material begins to heat, there are more photons and overall probably more energy going out. (I'm not giving an answer here, just some thoughts.)