The hunt for asteroid impacts on the moon heats up with new observatory

I assume that impacts should be happening over the whole lunar surface. Is the lack of any impacts detected north & south of 60 degrees an artifact of the viewing instruments or a giant cosmic coincidence?
 
Apr 18, 2020
128
23
4,585
Visit site
Not sure it's a good assumption that impacts would be distributed evenly. For instance, the fact that the same side of the moon always faces Earth suggests that that side might get fewer impacts, since Earth's gravity would scoop up or divert many bodies on a direct path to that side. I suspect that mapping the full effect of Earth's gravity could reveal a pattern of lighter/heavier impacts on the lunar surface.
 
  • Like
Reactions: Torbjorn Larsson
Not sure it's a good assumption that impacts would be distributed evenly. For instance, the fact that the same side of the moon always faces Earth suggests that that side might get fewer impacts, since Earth's gravity would scoop up or divert many bodies on a direct path to that side. I suspect that mapping the full effect of Earth's gravity could reveal a pattern of lighter/heavier impacts on the lunar surface.

Good question and answer!

If we look at the typical speed of an asteroid that hit Earth, it drops down to something like 20 km/s, which is Earth orbital speed. In essence Earth, and I expect Moon, acts like giant fly swatters with an overlay of own speed of impactor in relation to Sun as well as Earth gravity as bolide says.

Given that NELIOTA looked 149 hours before seeing its 100th flash (or about once every hour for 5+ cm impactors), I expect to see the impacts distributed over the whole surface in relation to the orbital plane [ http://www.esa.int/Safety_Security/100th_lunar_asteroid_collision_confirmed_by_second_telescope ]. That would tend to cluster the impacts towards the equator (perpendicular vs horizontal surface projection), as well as screen the emission from the impact with a corresponding angle, as well as becoming hidden behind any topography. I expect a sharp drop off in seen impacts towards the poles - a combined impact and emission sin^2 angle effect in a 1 D slice and it is "2D" emission cones so radiation dispersal in the angled projection becomes even worse I think (haven't worked the problem), as well as Moon having lots of crater walls et cetera that starts to come in the way - and that is what we seem to see here.
 
Last edited:

TRENDING THREADS

Latest posts