Oh, right - tha's actually a good idea & one can measure rotation rates of asteroids: https://en.m.wikipedia.org/wiki/List_of_fast_rotators_(minor_planets) http

Oh, right - tha's actually a good idea & one can measure rotation rates of asteroids: https://en.m.wikipedia.org/wiki/List_of_fast_rotators_(minor_planets) https://en.m.wikipedia.org/wiki/List_of_fast_rotators_(minor... BTW, the recently discovered extra-solar asteroid also had quite some rotation IIRC.