## Nongravitational Effects on Cometary Motion due to Jupiter

Protecting the Earth against Collisions with Asteroids and Comet Nuclei, In: A. M. Finkelstein, W. F. Huebner, V. A. Shor (Eds) Proceedings of the International Conference “Asteroid-Comet Hazard-2009”, StP: Nauka, 134–138 (2010)

**Keywords**:
Very Long Baseline Interferometry (VLBI), Near Earth Objects (NEOs), cometary motion, nongravitational effects, additional acceleration of comets, in the vicinity of Jupiter, gravitational perturbations, nongravitational perturbations, a function of the jovicentric distance, osculating orbital elements, the least squares method, comet positional observations, numerical dynamical theories of comets, Harrington-Abell, Kopff, Shoemaker-Levy 9, equations of motion, standard derivations of residuals

### Abstract

The problem of linking cometary apparitions before and after the approach of a comet to Jupiter was investigated. A hypothesis of possible existence of additional acceleration, perturbing the motion of comets in the vicinity of Jupiter, was considered. This nongravitational perturbation is described by a function of the jovicentric distance, written in a standard "force law" form. The values of its coefficients are determined along with the osculating orbital elements by the least squares method in the process of fitting the comet positional observations. Numerical dynamical theories of comets Harrington-Abell, Kopff, and Shoemaker-Levy 9 were constructed. An additional acceleration in the cometary motion in the vicinity of Jupiter was included into the equations of motion along with the well-known gravitational and nongravitational perturbations. It was shown that inclusion of nongravitational acceleration enables one to reduce standard derivations of residuals for all considered objects