Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two bodies gravitational system with variable mass and
  damping-antidamping effect due to star wind   We study two-bodies gravitational problem where the mass of one of the bodies
varies and suffers a damping-antidamping effect due to star wind during its
motion. A constant of motion, a Lagrangian and a Hamiltonian are given for the
radial motion of the system, and the period of the body is studied using the
constant of motion of the system. An application to the comet motion is given,
using the comet Halley as an example.

13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th