Is asteroid 951 Gaspra in a resonant obliquity state with its spin increasing due to YORP?

Asteroid 951 Gaspra appears to be in an obliquity resonance with its spin increasing due to the Yarkovsky‐O'Keefe‐Radzievskii‐Paddack effect (YORP effect, for short). Gaspra, an asteroid 5.8 km in radius, is a prograde rotator with a rotation period of 7.03 hours. A 3 × 106 year integration indicates that its orbit is stable over at least this time span. From its known shape and spin axis orientation and assuming a uniform density, Gaspra's axial precession period turns out to be nearly commensurate with its orbital precession period, which leads to a resonance condition with consequent huge variations in its obliquity. At the same time, its shape is such that the YORP effect is increasing its spin rate. YORP may be a reason for small asteroids entering resonances in the first place: they speed up or slow down and fall into resonances. The continued action of YORP probably ultimately causes asteroids to leave resonances, so that they are quasi‐stable states.