Comment by jcgrillo

3 days ago

What would zapping a satellite with a laser achieve? I suppose if you get it hot enough to melt everything, without anything flying off, then it would turn into a spherical drop of molten scrap... but then what?

You ablate part of it on the prograde side to create a small retrograde thrust which will deorbit it.

I think the right move is to merge this approach with goo blobs. We launch a large goo blobs or nets into a few strategic geostationary orbits and now you only have to ablate objects so they hit the goo then deorbit the goo once it is full (or just leave it there) as they would be large known orbits.

I assume the poster means to change its trajectory.

  • By adding energy (and momentum)? That seems unlikely to work. I guess you could try to shoot at things headed towards you over the horizon, to slow things down?

    I was assuming it was to vaporize things to make the re-condensed remnants small and dispersed enough to be less of a problem. Though that seems like a tough problem if you have to stay trained on an orbiting bolt for any length of time, as the atmosphere wobbles your laser around.

    • Well the targeting angle could be low to the horizon, aiming into oncoming debris, reducing its orbital velocity, so that it deorbits faster. The vertical component of the vector would be minimized. A low angle reduces laser efficiency due to more atmospheric interference, but oblique enough it would work. Nearly all man-made satellites (and space junk) orbit in the direction of Earth's rotation because of launch boost, which makes this easier.