关于北宋的几个火流星群

On several Bolide Groups in the Northern Song Dynasty

本文根据北宋一千二百多条流星记录，先证明它们都是火流星或“准火流星”。其次根据流星群的条件，定出三条划分火流星群的原则。最后挑选其中一条原则，考察北宋诸火流星记录，选出五群符合原则的火流星，先讨论和确定其出没点的位置，然后按流星运动路线相交法定出它们的辐射点。

Based on more than 1, 200 records of meteors in the Northern Song Dynasty, they are allproved to be bolides or quasi-bolides. And then, three principles are established for dividingbolide groups according to the condition of meteoric group. And finally, one principle is chosen to inspect five groups from bolide records of the Northern Song Dynasty, the pointswhere they appeared and disappeared are discussed and defined, and then the points wherethey radiated are defined by intersection method of meteor trajectory.