The cometary ejection play a crucial role in formation and evolution of the meteoroid stream.彗星的喷发速度在流星群的演化过程中起着重要作用....

meteoroid的音标：meteoroid的英式发音音标为：['mi:tjərɔɪd]meteoroid的美式发音音标为：['mitɪərˌɔɪd]...

micrometeoroid的音标：micrometeoroid的英式发音音标为：[maɪkrəʊ'mi:tɪərɔɪd]micrometeoroid的美式发音音标为：[ˌmaɪkroʊmɪtɪrˌrɔɪd]...

n.流星体...

n.微流星体...