光年

The new technique reduced the distance ladder to three "rungs":(1) The distance to galaxy NGC4258 is measured using straightforward geometry and Kepler's laws;(2)Cepheids in six more distant galaxies are used to calibrate the luminosity of Type Ia supernovae;(3) The Hubble constant is measured by observing a brighter milepost marker, Type Ia supernovae, in more distant galaxies hundreds of millions of light-years away, embedded in the expanding universe.

这种新技巧简化了距离跳跃为三个&阶梯&：1、星系NGC 4258的距离采用开普勒定律和简单直接的几何方法精确测量；2、在6个更远的星系中的造父变星用来校准Ia超新星的光度；3、深嵌于数亿光年外的膨胀宇宙中的星系中的Ia超新星——一种遥远而明亮的量天尺，被用于精确测定哈勃常数。

Because NGC 4603 is much farther away than the other galaxies studied with Hubble by the Key Project team, 108 million light-years, its stars appear very faint from the Earth, and so accurately measuring their brightness, as is required for distinguishing the characteristic variations of Cepheids, is extremely difficult.

由于它远在1.08亿光年外，远超项目组团队研究的其他星系，故此恒星变得非常黯淡，而任务要求必须正确测定其中的特定变星——造父变星——的光度，显得格外困难。

The galaxy is of type Sc and it is very nearly face-on. The distance to M51 is about 9 Mpc (or about 30 million light years), and it is moving away from us at about 500 km/s.

银河是Sc类型，而且它几乎非常面对着。M51的距离大约是9Mpc(或大约3千万光年)，而且它是以大约500 km/s速度移动远离我们而去。

However, spanning about 50,000 light-years, NGC 55 is seen nearly edge-on, presenting a flattened, narrow profile in contrast with our face-on view of the LMC.

而NGC55大约覆盖了5万光年，从侧面看去，扁平狭窄的外观与大麦哲伦星系正面外观形成鲜明的对比。

Explanation: In visual appearance, M74 is a nearly perfect face-on spiral galaxy, about 30 million light-years away toward the constellation Pisces.

正如我们所见，M74是一个几乎正面朝向我们的旋涡星系，它位于双鱼座方向，距离我们约3000万光年。

The object is actually a shell of gas and dust that has been blown off by a faint central star, lying around 700 light-year away in the constellation of Aquarius.

该星云实际上是一个衰亡中的恒星释放出的气体和灰尘，位于离地球约700光年的宝瓶座星系。

The object is actually a shell of gas and dust that has been blown off by a faint central star, lying around 700 light-year away in the constellation of Aquarius.

该景象实际上是一个衰亡中的恒星释放出的气体和灰尘，位于离地球约700光年的宝瓶座星系。

Measured at 36 light years across, this young supernova remnant has a rapidly expanding shell of hot gas at few million degrees.

这个年轻的超新星残骸横跨三十六光年，它有一个正在急速膨胀，温度高达数百万度的热气体外壳。

An emission nebula that contains much dust, the Keyhole Nebula is roughly 9,000 light years distant.

钥匙洞星云是一个包含有大量星际尘埃的辐射星云，距离地球大约9000光年。

The cluster lies 2600 light-years from Earth in the constellation of Monoceros.

这棵&树&实际是距离地球2600光年的麒麟星座。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。