Two papers to report in the May issue of New Astronomy (vol. 116):
Agbogidi, B. R. Vincent, A. E. Afere, B. A. E. et al. Equilibrium points in the perturbed rotating mass dipole system with oblateness art. 102344 .2024.102344
Wang, N. Lou, K-R. Xue, Z-Y. et al. The distortion solution for the 1-m telescope at Yunnan Observatory and its application to the positional measurement of four main-belt asteroi… art. 102351 .2024.102351
Agbogidi et al. consider the gravity field (and thus, orbits) around a dipole- that is, a central body with two lobes, like 67P/Churyumov-Gerasimenko, or (486958) Arrokoth. For a flyby or distant orbiter, this is just academic, but for close orbits and landers, the dynamics grow nontrivial. Heck, even (433) Eros departed from spherical enough to force a high-order gravity solution for the NEAR Shoemaker probe.
Now, the other end of mankind’s reach: telescopic observations and their data reduction. When a body like an asteroid is observed from the ground, it is nominally a point (“unresolved”), but the effects of our atmosphere blur it into a fuzzball. Hard to measure a fuzzball, eh? But with enough observation, we can take the average of the fuzz, and derive a nominal point from that statistical average. Wang et al. do so for the Yunnan telescope and its site. As with other observatories, it takes work to find that point.