[bmitc]

> There is no liquid water on the moon.

That is not definitive. There is frozen water and even water that sublimates on the bright side of the Moon. And the internal core of the Moon is quite hot. It is not beyond the realm of possibility that there are pockets of liquid water.

> Compared to what nature does to the surface, a few rocket bodies and impactor probes is a rounding error.

It's not an excuse. I also didn't comment about the impact itself, although it would be interesting to see a comparison to the meteors it gets hit by compared to the rocket shell, comparing speeds and size.

[ggreer]

I was obviously referring to the surface of the moon, where impacts happen. It is impossible for liquid water to exist on or near the surface, as the lack of atmosphere means that water either freezes or sublimes (and is then split into hydrogen & oxygen atoms by solar wind, causing the hydrogen to escape into space).

Yes, it is physically possible for liquid water to exist deep below the poles of the moon, but it would escape over time. Since there’s no way for any underground water to be replenished, and the moon is slowly cooling, it is very likely that all water on the moon is in non-liquid form (either ice, chemically bound up in rocks, or trace amounts of vapor that is soon to escape into space).

Meteors impact at 5-10x the velocity of the rocket body, meaning they have 12-50x more kinetic energy for the same mass. Their sizes vary, but a 4 ton booster traveling at 2.43km/sec is not going to be the most energetic impact on the moon this year.