YARKOVSKY EFFECT AND ITS ESTIMATION
The surface temperature of a rotating asteroid varies with time as it absorbs and then reradiates the energy from Solar irradiation. The recoil force of the thermal radiation from each surface element thus depends on its geometry and temperature, which in turn are determined by its thermal, physical and dynamical parameters. The recoil force may change the asteroid’s orbit (Yarkovksy effect) and rotation (YORP effect). In general, the computation of these two effects for irregularly shaped asteroids is very complicated. In this report, we briefly introduce the influences of these effects on the dynamics of asteroids, and we propose a shape index for asteroids with any shape, with which the Yarkovsky effect can be easily estimated.
Additional information: Prof Man Hoi Lee, mhlee@hku.hk