1.
Seyfert galaxies are energetic because they have a central black hole surrounded by a ring of gas.
赛非星系能量巨大，因为在其中心有一黑洞，黑洞周围则环绕着环状星云。
2.
As matter is sucked from the ring into the hole, part of it is converted into energy, which is radiated into space.
环状星云的物质在吸收到黑洞中去的过程中，一部分转化成了能量，而这一能量向宇宙空间辐射。
3.
Theorists, however, have had trouble trying to establish how the matter in the ring loses enough of its orbital motion to fall into thehole in the first place.
然而，理论工作者首先遇到的难题是无法确认环状星云的物质是如何偏离自己的轨道而掉进黑洞的。
4.
The quality or condition of being nebulous.
星云状态星云的性质或状态
5.
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。
6.
The Crab Nebula lies about6,500 light-years away in the constellation Taurus.
蟹状星云距离金牛座大约6,500光年远。
7.
The spiral nebulae were scratches left by the grinder.
螺旋状的星云是研磨者所留下的痕迹.
8.
The nebulous, luminescent cloud containing the nucleus and constituting the major portion of the head of a comet.
彗发星云状的发光云体包括彗核、彗星头部的重要部分
9.
Such tumultuous, often visually spectacular, interstellar regions surrounding youthful stars are known as gaseous nebulae.
这种环绕着年轻星的动荡且常常是壮观的星际区域，叫做气体星云。
10.
In fact, the cosmic Crab is now known to be a supernova remnant, an expanding cloud of debris from the death explosion of a massive star.
实际上,现在我们知道蟹状星云是超新星爆发的遗迹,即一个巨大恒星死亡后爆炸的残屑云。
11.
Environmental Evolution Records of Biomakers from Lacustrine Deposits of Xingyun Lake Yunnan
云南星云湖沉积记录的近代环境变化:来自正构脂肪醇的证据
12.
The general shape of the average nebula is that of a thin circular disk somewhat thick in the center.
星云最常见的形状是中间较厚边缘较薄的圆盘。
13.
We have identified the Crab Nebula as the debris of this explosion.
我们已证明蟹状星云就是这次爆炸的遗迹。
14.
1 the clouds from which stars are born are as dense as the space around earth.
孕育恒星的星云的密度和环绕地球的太空的密度是一样的。
15.
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。
16.
Many objections can be raised to this picture of planetary nebula formation.
形成行星状星云的这一图象可能会引起许多异议。
17.
These unusual celestial bodies are composed of single or multiple nebulous patches, some nearly stellar in appearance.
这些异常天体，由单个或多个星云状斑组成，有的外形近于恒星。
18.
New Gypsophila paniculata Cultivars ‘Yunxing 17’ and ‘Yunxing 23’
满天星新品种‘云星17’和‘云星23’