The Leonid meteoric shower has been the most famous meteoric shower. The main characteristics of the stream are well known, being very spectacular displays in recent years. In this paper, the authors aim at searching the dynamic origin of the second peak of Leonids 1998. Firstly a dynamic model of the solar system is constructed, considering the perturbations of the nine major planets and the Moon, Post-Newtonian effects and the figure effect of the Earth. For the motions of cornet and meteoroid, the non-gravitational effect and radiation pressure effect are taken into account separately. Secondly, the orbit of Comet Tempel-Tuttle is determined by using the observation data of this apparition. Finally, assuming an isotropic ejection model of comet, the authors simulate the motion of the meteoric stream and discover that the particles aged 2-revolutions erupted with velocity 50m/s can befall Earth at 20h37m UT of Nov. 17, 1998, which form the main part of the second peak of Leonids 1998.
Matching cometary ejection processes to the Leonids 1998-2001 using a hybrid numerical model
