星云

The sands of time are running out for the central star of this hourglass shaped planetary nebula .

对产生这个行星状星云的中心恒星来说，它的来日的确是不多了。

The term planetary nebula , used to describe this general class of objects , is misleading .

这一类天体有一个令人误解的术语，那就是&行星状星云&。

A planetary nebula represents the final stage in the evolution of a star similar to our Sun.

行星状星云是类似于太阳的恒星的演化归宿。

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。

The Sun is expected to go through its own Planetary Nebula phase .

再过五十亿年，太阳预期也会进入行星状星云阶段。

The star primarily responsible for this interstellar sculpture can be found in the planetary nebula's center.

至于造成这座星际雕塑品的始作俑者，我们可以在行星状星云的中心看到此恒星的尊容。

The Helix planetary nebula is constructed from matter ejected by a dying Sun-like star, almost 690 light-years away.

这种螺旋行星状星云是由一颗即将消逝的恒星所喷发出来的大量物质所有形成的，大概距离地球690光年。

These new developments enable us to identify the first instance of symmetry breaking in the evolution from AGB to planetary nebula.

这个新发现使我们能够鉴认AGB星从打破球对称结构到最终形成行星状星云的最初一步。

In fact, 21st century astronomers would classify 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.

事实上，21世纪的天文学家将该天体归类为行星状星云，但是它也不是一颗行星，尽管通过小型望远镜看，它的外观可能呈圆形、类行星状。

Well, 20th century astronomers would classify 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.

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，只是用小型的望远镜观测时，它具有行星的圆盘状外观而已。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。