Although there are still many unanswered questions about black holes， scientists have discovered many interesting facts about them.

盡管黑洞仍是未解之謎，但科學(xué)家已經(jīng)發(fā)現(xiàn)了許多有關(guān)它的趣事。

Why do black holes appear black？

為什么黑洞是黑色的？

Color is an effect of light reflection—a natural phenomenon. It is why we perceive some things as red， some as blue， and others as green. Black holes do not reflect light， so they appear black.

顏色的呈現(xiàn)是光折射的效果——一種自然現(xiàn)象。這就是為什么我們可以看到不同顏色的事物，紅的、藍(lán)的、綠的。但黑洞不折射光，因此它是黑色的。

Why are they holes？

為什么黑洞被稱之為“洞”？

On Earth， gravity helps us stay grounded. On the moon， however， there is very low gravity. That is why astronauts can jump very high on the moon. Black holes have very strong gravity—so strong that no object can escape being sucked into it.

在地球上因為有引力的幫助，我們才能站在地面上。然而，在月球上，引力微弱到幾乎不存在。因此登月的宇航員才可以在月球上跳得很高。黑洞有著很強的引力，強到幾乎能把所有東西吸進去。

How do black holes come into existence？

黑洞是如何產(chǎn)生的呢？

One way black holes form is from gravitational collapse. Theyre created when stars explode and collapse on themselves. If these stars have a very large mass， they form black holes.

黑洞形成的一種方式是由引力塌陷引起。它們是由于天體爆炸并自我塌陷形成的。如果這些天體的質(zhì)量夠大，那它們就會形成黑洞。

Do black holes differ in size？

黑洞大小不一致嗎？

Yes， they do. There are four types of black holes： micro， stellar， intermediate mass and supermassive. If black holes attract many stars or combine with other black holes， they become very big. These are called supermassive black holes. Scientists say there is a supermassive black hole at the center of the Milky Way.

沒錯！有四種大小的黑洞：微型的，一般大小的，中等大小的以及超大的。如果黑洞吸引了許多星際物質(zhì)或者與其他黑洞結(jié)合，它們就會變得非常大。這就是超大黑洞?？茖W(xué)家稱在銀河系的中心有一顆超大黑洞。

Can black holes disappear？

黑洞會消失嗎？

A theory claims that they can disappear due to radiation. But this has not been proven yet.

There are many things we dont know about space， and scientists are still working on discovering new and interesting things. Maybe you will become a scientist and be the one to find answers to these questions！

理論上來說黑洞會因輻射消失，但是這未被證實。

太空中還有好多我們所未知的，科學(xué)家也仍然在探索新的、有趣的事物。將來也許你會成為一名科學(xué)家，去解答這些未解之謎！

Word Study

suck /s?k/ v. 吸;吮吸

She was noisily sucking up milk through a straw.

collapse /k?'l?ps/ v. & n. 倒塌;塌陷

The roof collapsed under the weight of snow.

The walls were strengthened to protect them from collapse.