

Asteroid Ryugu
The Hayabusa 2 target asteroid (162173) Ryugu displays a strange diamond like shape, at least from the sunny side explored so far.
Time for me to reuse the code developed for comet 67P/Churyumov-Gerasimenko and to compute the gravitational potential (with added centrifugal term, assuming a 7 h rotation period). The rotation weakens the gravitational potential in the equator regions. Otherwise on the triangular faces the potential minima are close to the centers of the triangle.
Update: new JAXA images, an animation of the rotation, and a shape model extracted by Doug Ellison. This allows me to recompute the effective gravitational potential (assuming a uniform density):