A screw-like meteoric train photographed by double-station observations

The double-station observation of a meteor is a kind of method for measuring the physical parameters of the meteor effectively. Four special groups of photographs about meteoric trains taken at two stations during Leonids 2001 have been collected. One representative group of them has been measured and analyzed in detail. The results reveal that this train has a screw-like structure and looks to have many spoke beams. The train moves forward in the form of left-hand screw. The horizontal drift velocity northward is 29.6 m s−1 and the vertical drift velocity upward is 12.3 m s−1. In addition, the material of the meteoric train has an outward expanding velocity up to about 79 m s−1. The possible explanation is that the persistent meteoric train is disturbed by the high altitude wind.