After I posted that, I did some more research to see how typical it is, over longer time periods, that our nearest star is about 4 ly away. That seems to be abo

After I posted that, I did some more research to see how typical it is, over longer time periods, that our nearest star is about 4 ly away. That seems to be about average spacing for our part of the galaxy, but it turns out in a little over a million years, a star about half the size of the sun will pass around 0.15 ly away or 10,000 AU, which is far outside the kuiper belt, but solidly though the middle of the inner oort cloud, and will leave a wake of scattered comets and asteroids, some of which will rain down on Earth. https://en.wikipedia.org/wiki/Gliese_710 https://en.wikipedia.org/wiki/Gliese_710