This isn't meant to endorse such a project, just speculate on whether or not it's possible.

 

Suppose Earth disposed of all its nuclear weapons by firing them at Mars or at craters on the moon. The thermal radiation would presumably be at least partly absorbed. Would there be a layer of molten rock that would then solidify in a semi-spherical shape perpendicular to these planets' gravity, sort of like the almost-flat manner in which ponds freeze over, or would it just sublimate directly into gas?

 

If the former, would this be functionally equivalent to a convex mirror? Would we then have a "virtual image" of the sun at night that would be smaller than the sun and brighter than the moon, and/or contain the same proportion of colours of the sun's spectrum? Or is the moon's absorption of UV rays more a function of its moon rock material than of its diffuse-reflective nature?

56 minutes ago, ScienceNostalgia101 said:

Would there be a layer of molten rock that would then solidify in a semi-spherical shape perpendicular to these planets' gravity, sort of like the almost-flat manner in which ponds freeze over, or would it just sublimate directly into gas?

Even if you did that, the planet would still keep its spherical shape overall. 

On 10/20/2018 at 8:13 PM, pavelcherepan said:

Even if you did that, the planet would still keep its spherical shape overall. 

True, but I was wondering more about convex-mirror-esque reflection than about shape.