In a nutshell, Napier’s study shows how comets are likely to fragment and lose considerable mass during encounters with the inner Solar System. The debris trail can expand to a cross section larger than Earth, increasing the odds of impacts with Earth. Also, the debris has considerable impact energy. But over time, that energy weakens, and the debris trail contracts again.
~Evan Gough, Universe Today, April 13, 2020
Just a quick post of a great article from last year. Evan Gough does a fantastic job describing a series of events that are just now entering the public imagination.