Mm-hmm.

And sometimes, um, these stars are on quite tight orbits, and they can even spiral into each other and, and merge together into a single star.

And we have seen this happen in the Milky Way.

Um, and when it happened, it was accompanied by this sort of, um, long and quite red signal-

Right, right, right.

Um, but yeah.

So a- anyway, there's-- This is why I say, you know, when people ask that I work on shock waves, because, um, there's all these sorts of different systems in astrophysics, um, where we expect to find shock waves, and we expect them to be bright and, um, so rather than picking a favorite, I just say that I work on the-