用武汉流星雷达观测象限仪座流星雨期间的流星速度

Observation on Meteor Velocities of the Quadrantid Meteor Shower by Using the Wuhan Meteor Radar

利用武汉流星雷达,首次成功地观测了象限仪座流星雨及流星雨期间的流星速度,讨论了利用单站全天空流星雷达观测流星雨的相关问题．从观测结果可以发现此次象限仪座流星雨发生在2004年1月4日的0000-0800LT,其中流星峰值出现在0400LT,而且通过流星雷达观测到的流星雨期间的流星回波平面推测得到的流星雨辐射点也与该流星雨的理论辐射点位置对应非常好．利用流星回波振幅的Fresnel振荡方法计算了此次流星雨期间观测到的流星的速度,分析了该流星速度的分布,这次流星雨期间观测到的流星速度主要集中在10-30km／s,可以看出这种速度分布是由流星雨进入地球大气的初始速度和流星在大气中的减速过程共同决定的．最后研究了流星速度随高度的变化,并且由此讨论了地球大气对于流星体的减速作用．

The Quadrantid meteor shower and the meteor speed during the period of this meteor shower are successfully observed using the Wuhan meteor radar for the first time, and then the correlative questions of observing meteor shower using the all-sky meteor radar are also discussed. The observational result shows that this Quadrantid meteor shower occurs between 0000 to 0800 local time in January 4, 2004, with meteor echoes peaking at 0400 local time. Moreover the meteor shower radiant derived from the meteor echoes plane, which is formed by the whole meteor echoes observed by the meteor radar during this shower, accords well with the theoretic radiant of this meteor shower. The meteor speeds during this period of this shower are calculated by the amplitude Fresnel oscillation method of the meteor echoes, and then the meteor speed distribution is analyzed, revealing the meteor speed observed during this shower mainly concentrated between 10-30km/s, which is discovered to be controlled by the meteor initial velocity entering earth＇s atmosphere combined with the meteor decelerating process in the atmosphere. Finally the meteor speed varieties with the height are studied, from which the decelerating effects of the earth＇s atmosphere on the meteor bodies are discussed