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 獅子座流星群聚集于一條狹長的區(qū)域內,以極為橢圓形的軌道環(huán)繞太陽運行,周期約為
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,年歷內亦列出曙暮光的持續(xù)時間,以及春分、秋分、夏至、冬至、日食、月食、歷法、流星群及行星觀測等詳盡資料。
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型變質量天體軌道根數(shù)變化方程的一階和二階解對15個流星群軌道半長軸、近日點距離、軌道周期和近日點經度因太陽質量損失造成的每世紀的長期改變效應做了數(shù)值計算,并得出計算結果。
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 其計算結果表明,太陽質量損失使流星群軌道半長軸每世紀的改變效應較明顯,它們同太陽距離的擴大影響值得關注,但對軌道周期的拉長每世紀的影響甚小,對近日點經度只有量級變化小到可以略而不計。
英文解釋
a transient shower of meteors when a meteor swarm enters the earth''s atmosphere 同義詞:meteor shower,