collapsing cloud 坍缩云
cometary burst 彗暴
cometary dynamics 彗星动力学
cometary flare 彗耀
cometary H Ⅱ region 彗状电离氢区
cometary outburst 彗爆发
cometary proplyd 彗状原行星盘
comet shower 彗星雨
common proper-motion binary 共自行双星
common proper-motion pair 共自行星对