Description
It is known that the Yarkovsky effect moves small asteroids to larger/smaller semimajor axes depending on their prograde/retrograde spins. The YORP effect influences asteroid spin periods and spin axis orientations so that they evolve in time. The alignment of the spin vectors and correlations of the spin rates, now known as Slivan states and observed among members of the Koronis family, are interpreted in terms of the YORP effect and spin-orbit resonances. Splitting asteroid families into prograde and retrograde groups has recently been proposed as a result of the Yarkovsky effect. Prograde and retrograde asteroids drift in different directions, and this has never been observed directly. The influence of the Yarkovsky and YORP effects should be observable among objects in asteroid families, especially in the Flora family, which lies close to the Sun and consists of many small objects. The Flora family asteroids were modelled using the lightcurve inversion technique. As a result the orientation of spin vectors, shapes, and sidereal periods of rotation were obtained.
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