What percentage of stars collide when two galaxy’s collide?

My understanding is that when two galaxy’s collide, typically, “very few” stars actually collide, because there is so much space inbetween stars.

Do any astronomers or physicists or probability experts out there have an approximate % range?

is it around 1-5% collide or what?

Just curious.

I think even less than that but the gravity effects of the stars on each other can cause a lot of havoc.

Ok then maybe 2 questions:

What percentage of the stars would collide?

What percentage of the stars would be effected enough to totally mess up/destroy life on any orbiting planets?

Almost no stars actually collide when galaxies pass through one another. With light-years separating individual stars, there is a huge amount of empty space in a typical galaxy, so collisions between stars are statistically insignificant. It would be impossible to estimate how many life-bearing planets would be affected, though, since we have no idea how common life is in the universe, or even in our own galaxy. Assuming, say, one star in a million has a planet which supports life, I’d say again the odds of one being affected to the point of destroying all life on it are miniscule. This would probably only happen if the planet in question were to be ejected from it’s parent star system.

I agree with Q.E.D. – but the number of new star formations appearing in the Antennae Galaxies certainly makes you wonder about overall radiation levels and just what might have been destroyed to create the new starstuff.

BTW, the above link has a computer simulation movie on how the present state of the Antennae Galaxies might have been come about during the collision.

There are more collisions that are due to infall spiralling of binaries than due to the two galaxies colliding by an inordinate number of orders of magnitude. And the number of events of spiralling binaries infall spiralling is somewhere near 1 per century per 1000 galaxies or so.