Most of the meteoroids of the leonid meteor stream concentrate in an elongated thin ribbon - like region . the stream orbits around the sun in an elliptical orbit with a period of about 33 years 狮子座流星群聚集于一条狭长的区域内,以极为椭圆形的轨道环绕太阳运行,周期约为
The duration of twilight , details of equinoxes , solstices , eclipses , information on calendar , observation of meteor streams and planetary phenomena as well as climatological " normals " of hong kong and some major cities for each month of the year are also given in this publication 此外,年历内亦列出曙暮光的持续时间,以及春分、秋分、夏至、冬至、日食、月食、历法、流星群及行星观测等详尽资料。
The numerical computation for the secular variable of the semi - major axis , solar distance at perihelion , orbital periods and longitude of perihelion has been made for fifteen meteor streams by using the solution of gylden - meshcherckii equations 利用g - m型变质量天体轨道根数变化方程的一阶和二阶解对15个流星群轨道半长轴、近日点距离、轨道周期和近日点经度因太阳质量损失造成的每世纪的长期改变效应做了数值计算,并得出计算结果。
The results show that the solar mass - loss extends the semi - major axis , the distance at perihelion and orbital periods of the meteor streams , especially , the extensive influence on the semi - major axis is not overlooked , but this influence on other orbital elements may be neglected 其计算结果表明,太阳质量损失使流星群轨道半长轴每世纪的改变效应较明显,它们同太阳距离的扩大影响值得关注,但对轨道周期的拉长每世纪的影响甚小,对近日点经度只有量级变化小到可以略而不计。
英文解释
a transient shower of meteors when a meteor swarm enters the earth''s atmosphere 同义词:meteor shower,