英语听力：2013-10-16 地平线：黑洞吞噬—12

 If there's a black hole at the center of our galaxy¹, that's gonna force these objects that are really close to the black hole to move much faster than they would move if there were no black holes. So the first thing you wanted to see is there are very fast moving objects where you think the black hole was. So with our pictures that we took what you can measure is how these stars move on the plain of the sky. You take one picture. You come back a year later. You take another picture. You see where they've moved to. And what we're seeing in this box are that there are stars that are moving incredibly quickly. That was the first evidence of, for the black hole. 

 

Once everything had been plotted out, this is the map of the galactic center they were able to produce. It showed that stars were hurtling around in very fast and tight orbits. But what Ghez was interested in was what they were circling around. 

 

If there is a black hole, there is a further prediction you can make about what these stars are gonna do. They are gonna move around the black hole on very short periods. In another words, you are gonna be able to see them move on more than just straight lines as part of their travel around the black hole. These stars are gonna move around the black hole because of the gravity just like planets move around the sun. 

 

There is only one thing that has the shear² force of gravity to compel such huge stars to veer³ round on such tight trajectories⁴. 

 

So what we see is that indeed you can, you see these stars were vibrant⁵. In fact, in these images you can actually tell where the black hole was. The black hole was at the center of the focus of these orbits.

1 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。

2 shear   

n.修剪，剪下的东西，羊的一岁；vt.剪掉，割，剥夺；vi.修剪，切割，剥夺，穿越

参考例句：

• Every spring they shear off the sheep's wool and sell it.每年春天他们都要剪下羊毛去卖。
• In the Hebrides they shear their sheep later than anywhere else.在赫伯里兹，剪羊毛的时间比其他任何地方都要晚。

3 veer   

vt.转向，顺时针转，改变；n.转向

参考例句：

• He is unlikely to veer from his boss's strongly held views.他不可能背离他老板的强硬立场。
• If you fall asleep while driving,you'll probably veer off the road.假如你开车时打瞌睡，可能会驶离道路。

4 trajectories   

n.弹道( trajectory的名词复数 )；轨道；轨线；常角轨道

参考例句：

• To answer this question, we need to plot trajectories of principal stresses. 为了回答这个问题，我们尚须画出主应力迹线图。 来自辞典例句
• In the space program the theory is used to determine spaceship trajectories. 在空间计划中，这个理论用于确定飞船的轨道。 来自辞典例句

5 vibrant   

adj.震颤的，响亮的，充满活力的，精力充沛的，(色彩)鲜明的

参考例句：

• He always uses vibrant colours in his paintings. 他在画中总是使用鲜明的色彩。
• She gave a vibrant performance in the leading role in the school play.她在学校表演中生气盎然地扮演了主角。