Today on the arXiv:
Seligman et al. 2023, "Dark Comets? Unexpectedly Large Nongravitational Accelerations on a Sample of Small Asteroids" - https://arxiv.org/pdf/2212.08115.pdf
Suggests outgassing from asteroid #1998KY26, to be visited by Hayabusa 2, at a level #TeamRadar could not detect.
How could a ~30 m near-Earth asteroid like #1998KY26 hold on to volatiles long enough to still be outgassing?
Hmm...
Addendum:
Seligman et al. 2023 discuss at length other things that can push small asteroids around: thermal fracturing throwing dust out, asymmetric meteoroid bombardment, etc.
Resolving this will probably have to wait for @[email protected] / @[email protected] to get to #1998KY26.
Michael Busch