Despite how little neutrinos interact with matter, my understanding is that much of the pressure that actually drives a supernova explosion is caused by them. T

Despite how little neutrinos interact with matter, my understanding is that much of the pressure that actually drives a supernova explosion is caused by them. Their mean free path in lead is about a light year, so imagine how many neutrinos must be produced in a supernova. Now remember that we only detected 11 of them here on Earth using detectors that are massive on a human scale. Space is huge.