Spin and shape model of (98943) Torifune

This procedure provides realistic uncertainties for the determined sidereal period, pole direction, and shape parameters. We refine the sidereal period to P_sid_=5.0215221^+0.0000011^_-0.0000007_h and confirm a prograde spin state with the axis near the north ecliptic pole. The nominal pole solution is (lambda, beta) = (314 deg, +84 deg), with a 5.4 deg angular uncertainty.

The dynamically equivalent ellipsoid has a/b=1.66^+0.03^_-0.07_, whereas its polar axis remains less well constrained, with b/c=1.49^+0.44^_-0.29_. All quoted uncertainties correspond to the two-sided 95% intervals of the block-bootstrap distributions. The forthcoming Hayabusa2# flyby should enable direct evaluation of which elements of this pre-encounter convex inversion model are robust, particularly the pole orientation and global silhouette, and may help constrain the remaining uncertainty in the polar dimension of the body.