About the Yarkovsky effect in the dynamics of asteroid (99942) Apophis

Abstract

The influence of changes in the rotational state of asteroid (99942) Apophis during its next approach to the Earth in 2029 on the magnitude of the Yarkovsky effect acting in the orbital dynamics of the asteroid was studied. It is shown that changes in the speed of its own rotation and the orientation of the asteroid’s rotation axis, caused by a close approach to the Earth, can lead to variations in the magnitude of the Yarkovsky effect by several times. The average rate of annual change in the semimajor axis of Apophis’s orbit, caused by the Yarkovsky effect, after approach can range from −235 to −20 m/year.