[天]行星状星云

planetary nebula───[天]行星状星云

planetary nebulas───[天]行星状星云

Tarantula nebulae───蜘蛛星云；舞蛛星云

dark nebulae───[天]暗星云

galactic nebulae───银河星云

planetary activity───行星活动

planetary precession───[天]行星岁差

Horsehead nebulae───[天]马头星云

Tarantula nebula───蜘蛛星云；舞蛛星云

Planetary nebulae fade away gradually over tens of thousands of years.───行星状星云在数万年间逐渐衰老。

Planetary nebulae are a type of isolated gaseous nebulae possessing a fair degree of bilateral symmetry.───行星状星云是一类孤立的气体星云,具有相当程度的双侧对称性.

Stars that form planetary nebulae typically live for billions of years.───代表性的是，构成行星状星云的恒星已经存活了十亿年。

Planetary nebulae are not as airy and tranquil as their images suggest.───行星状星云并不如影像中所显现的那麽飘逸宁静.

L the Ring nebula in Lyra is the best-known of the planetary nebulae.───l天琴座中的环状星云是最著名的行星状星云。

Tne binary interactions play an important role in the formation and shaping of planetary nebulae ( PNe ).───在行星状星云形成过程中 双星 起着非常重要的作用.

Planetary nebulae are a type of isolated gaseous nebulae possessing a fair degree of bilateral symmetry.

Planetary nebulae fade away gradually over tens of thousands of years.