The libration points in photogravitational restricted three-body problem

The photogravitational restricted three-body problem in which the mass reduction factors of two primaries q₁, q₂ ε −∞,1] are studied and an analytic method to estimate the number of libration points and to calculate their location is given in this paper. The results show that in photogravitational restricted three-body problem, the number of libration points is from one to seven for different q₁ and q₂. As application, the motion of dust grain like comet tail in the solar system is also discussed. Project supported by the National Natural Science Foundation of China