Interesting engineering (/engineering science) from the AIAA’s Journal of Guidance, Control, and Dynamics. Yes, Journal of Guidance, Control, and Dynamics:
Negri, R. B. Prado, A. F. B. A. Shallow Encounters’ Impact on Asteroid Deflection Prediction and … p. 1341 /1.G007890
Zhao, C. Maestrini, M. Di Lizia, P. Low Thrust Optimal Control of Spacecraft Hovering for Proxim… p. 1457 /1.G008063
Space is a weird place. Gravity reaches to, oh, infinity, it’s a matter of how many decimal places you take your analysis. With no air, the number of relevant, viable decimal places is higher than one would assume. Perturbations of one mass by another are standard (non-) assumptions in space, and competent practitioners must account for surprisingly distant, small bodies. Negri et al. are competent space practitioners.
Hayabusa hovered (…mostly) by Itokawa. Hayabusa2 and OSIRIS-REx hovered by their respective asteroids. This cross-pollinates space world, via inspection/servicing satellites. Pollinate away, we’ve got plenty more asteroids to hover by!