Despite the short response by Irishman, this is actually a good question. There are two answers, (1) thermodynamical, and (2) microscopical:

(1) Thermodynamically, the meteor and the moon rock heat up to very high temperatures right after the moment of impact. Since rock is approximately a black body, it emits black body radiation, which depends on the temperature. If the temperature is high enough, this radiation is in the optical spectrum. However, this is not really an explanation, just a phenomenological description. To really understand what’s going on, we need to look at the atoms and electrons in the rocks:

(2) Microscopically, shockwaves through the rock excite the atoms and molecules in the rock to higher energy levels. When the electrons relax to lower energy levels, they emit photons. Hence the light.

I saw it reported as “We have it in mind that one of these things could hit the next moon base”. Well, the moon base is probably about as safe on any given day as a moon rocket of equivalent size, yes? Give or take the quantity of loose junk that we have successfully boosted into low earth orbit; a more bad place to be, if you worry about that. James White wrote a couple of science fiction stories about… well, I think “Deadly Litter” is one. So anyway… unlikely as it is, I suppose we still want to take precautions so we don’t lose a /whole/ moon base at a stroke.

I think I’d be more worried about radiation. So a deep underground moon bunker is good for both, right?

What you would name the new crater?

…I am assuming, of course, that every crater on the moon has a name, and I could be wrong on that.

The surface of the moon is nothing but craters, from the miles-wide impact basins to the tiny pockmarks of interplanetary dust which create the “softened” look of the surface. But if we can pinpoint this one yeah, it oughta get a name.