Causes of Asteroid (457175) 2008 GO98/362P Activity

Abstract

The orbit of an active asteroid (457175) 2008 GO98/362P was obtained taking into account non-gravitational acceleration based on the Marsden model. The presence of systematic deviations was revealed in the 2016 observations prior to the cometary activity. The possibility of a collision with a minor body was considered. For this, the momenta of reaching the minimum distances (MOID, Minimum Orbit Intersection Distance) between the orbits of the asteroid (457175) and 585 961 numbered, and 536 561 unnumbered asteroids (according to the status in the Minor Planet Center catalogs of observations as of October 2021) were found. The maximum number of orbital rendezvouses falls on the time when the asteroid was passing in the vicinity of the ascending node, which suggests the possibility of a collision leading to the fragmentation of the main body. Two separation scenarios are considered and orbit variation of the main body and possible fragments are estimated. For the formed fragment, the heliocentric velocity variation amounted to $dv=0.148$ m s${}^{-1}$ and non-gravitational acceleration was $A_{3}=-12.5\times 10^{-8}$ AU day${}^{-2}$. The main body dynamics did not vary significantly.