A Spiral Meteor Train

A spiral meteor train was successfully observed and photographed at two stations. The spiral was 4.17 ms in period and 461 m in diameter. We calculated the centrifugal acceleration and atmospheric drag of the meteoroid, and found that it is not the meteoroid but only the emitted gas which is making a spiral motion. A non-linear meteor trail may be curved or branched, if not spiral. We attempted a dynamic study. Since a meteoroid has a very large kinetic energy, compared to the force received from the atmosphere, its motion is not changed greatly.