行星状星云

在21世纪，天文学家会将它分类为行星状星云，但是实际上它也不是行星，只是用小型望远镜观测时，它具有类似行星的圆浑外观而已。

In fact , 21st century astronomers would identify it as a planetary nebula , but it 's not a planet either , even though it may appear round and planet-like in a small telescope .

从AGB星到行星状星云

From AGB Star to Planetary Nebula

这两个行星状星云（取这个名字是因为最初在18世纪时说这些物体外观类似行星）名为NGC6303，也叫蝴蝶星云，和NGC7027。

They 're two planetary nebulae ( so named because initially , these objects were first described as planet-like in the 18th century ) called NGC 6303 , or the Butterfly Nebula , and NGC 7027 .

双极行星状星云形成的Monte&Carlo分析

Monte - carlo analysis for the formation of bipolar planetary nebulae

形成行星状星云的这一图象可能会引起许多异议。

Many objections can be raised to this picture of planetary nebula formation .

行星状星云并不如影像中所显现的那麽飘逸宁静。

Planetary nebulae are not as airy and tranquil as their images suggest .

行星状星云NGC2242的红外辐射

Infrared Radiation of Planetary Nebula NGC 2242

和原行星状星云成协的致密反射星云

Compact Reflection Nebulae Associated with Protoplanetary Nebulae

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。

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

行星状星云实际上是一些即将消亡的恒星抛射出的气体外壳，在学术上与行星并没有什么关系。

These nebulae , which are not technically related to planets , are gas clouds forced outward by a dying star .

在图片的协助之下，科学家们有望揭开揭开行星状星云复杂的结构，以及其对称性背后的谜团。

And it is these that are helping scientists to resolve the outstanding mysteries of the complex shapes and symmetries of planetary nebula .

文中的表1包括100个发射线天体，其中的96个是发射线星系；其余的对象有3个行星状星云，1个发射线星。

We find a total of 100 emission-line objects , of which 96 are galaxies , the rest being 3 planetary nebulae and 1 star .

这个很有趣的结果指出，大质量恒星爆炸所产生的碎片云，其外观和某些小质量恒星所产生的行星状星云相似。

The intriguing result implies that the massive star 's explosion has produced a shape similar to what is seen in some planetary nebulae associated with lower mass stars .