30 A2+ the science of darkness

CHAPTER 1 The Dark WHAT DOES "DARK" MEAN? Jenny told her roommate Isabel, "Turn on the light. It's dark in here!" Isabel said. "Why? I like the dark. I like to sit and think in a dark room." "OK, but we're not living in the Dark Ages," Jenny said. "So turn on the TV!" "No, I think people use too much electricity," Isabel said. "You don't have to be in a dark mood about it," Jenny answered. "I'm not," Isabel said. "I'm just worried. Are you in the dark about what's going on in the world? We use too much energy! It's terrible." "I think you worry too much. You have dark circles under your eyes."

第一章黑暗“黑暗”是什么意思？ 珍妮告诉她的室友伊莎贝尔：“把灯打开。 这里太黑了！”伊莎贝尔说。 “为什么?我喜欢黑暗。我喜欢坐在黑暗的房间里思考。” “好吧，但我们不是生活在黑暗时代，”珍妮说。 “那就打开电视吧！”“不，我认为人们用电太多了，”伊莎贝尔说。 “你不必为此闷闷不乐，”珍妮回答说。 “我没有，”伊莎贝尔说。“我只是担心。 你对世界上正在发生的事情一无所知吗？ 我们消耗了太多的能源！这是可怕的。” “我觉得你担心得太多了。 你有黑眼圈。”

"Well, I think it's important." Isabel said. "I guess you're right, but, actually, I'm afraid of the dark!" Jenny said. "Afraid of the dark?" Isabel was surprised. "Come on... come outside with me." It was a pitch-dark night. The girls couldn't see in front of them. Finally, they got to the middle of the back yard. "Look up," Isabel said. The sky was completely black except for some stars. "Isn't it amazing?" "Well, yes, it is kind of beautiful," Jenny said. The word "dark" is used in many ways in English. It can describe something that doesn't have light. It can mean something is bad or evil. But what is darkness?

“嗯，我认为这很重要。” 伊莎贝尔说。“我想你是对的，但是，实际上，我怕黑！”珍妮说。 “怕黑？”伊莎贝尔很吃惊。 “来吧……跟我出去吧。” 那是一个漆黑的夜晚。 女孩们看不见前面的东西。 最后，他们来到了后院中央。 “抬头看，”伊莎贝尔说。除了几颗星星外，天空一片漆黑。 “这不是很神奇吗？”“嗯，是的，是有点美，”珍妮说。 “dark”这个词在英语中有很多用法。 它可以描述没有光的东西。 它可以表示某事是坏的或邪恶的。 但什么是黑暗？

CHAPTER 2 Dark Matters WHAT IS IN THE NIGHT SKY? Have you ever looked at the sky and thought about darkness? Is it nothing? Or is there something in the dark? Cosmologists try to answer questions about things in space. They even study the darkness in space. They say the universe is about 5 percent "normal" matter— things we can see, like Earth and other planets, and the sun and other stars. But about 70 percent of the universe is something called dark energy. Cosmologists are still studying what dark energy is. They have more questions than answers. Cosmologists think this dark energy fills space and shows that the universe is expanding. There is more dark energy in the universe now than there was before.

第二章暗物质夜空中有什么？ 你可曾仰望天空，想到黑暗？ 没什么吗？还是黑暗中有什么东西？ 宇宙学家试图回答有关太空事物的问题。 他们甚至研究太空中的黑暗。 他们说，宇宙中大约有5%是“正常”物质，即我们能看到的东西，比如地球和其他行星，太阳和其他恒星。 但是大约70%的宇宙是被称为暗能量的东西。 宇宙学家仍在研究暗能量是什么。 他们的问题比答案多。 宇宙学家认为，这种暗能量充满了空间，表明宇宙正在膨胀。 现在宇宙中的暗能量比以前要多。

If about 70 percent of the universe is dark energy and about 5 percent is "normal" matter, what is the rest of the universe made of? Cosmologists say the other 25 percent of the universe is dark matter. Dark matter has some weight, it's heavy so we know it's there. But it's invisible, we can't see it. It is very hard to study something that you can't see! One possible kind of dark matter is a brown dwarf. A brown dwarf is too big to be a planet and too small to be a star. Brown dwarfs are colder than stars, and they don't give off light that people can see. Cosmologists found them by using a telescope that finds heat. They found the first brown dwarf in 1995.

如果宇宙的70%是暗能量，5%是“正常”物质，那么宇宙的其余部分是由什么组成的呢？ 宇宙学家说，宇宙的另外25%是暗物质。 暗物质有一定的重量，它很重，所以我们知道它的存在。 但它是看不见的，我们看不见它。 研究你看不见的东西是非常困难的！一种可能的暗物质是褐矮星。 褐矮星太大而不能成为行星，又太小而不能成为恒星。 褐矮星比恒星更冷，而且它们不会发出人们能看到的光。 宇宙学家通过望远镜发现了它们。 他们在1995年发现了第一颗褐矮星。

Cosmologists do know a lot about one kind of dark matter black holes. In 1783, English writer and astronomer, John Michell, guessed that there were black holes. He called them "invisible stars." But cosmologists didn't find any black holes until 1971, almost 200 years later. Since then, they've found many black holes in space. It's very dark in a black hole. There's a lot of gravity there, too. There is so much gravity in a black hole that nothing can get out, not even light. This is why we can't see them. Cosmologists find black holes by looking at things around them. For example, stars and gases near a black hole move very fast.

宇宙学家确实对一种暗物质黑洞了解很多。 1783年，英国作家兼天文学家约翰·米歇尔猜测存在黑洞。 他称它们为“看不见的星星”。 但是宇宙学家直到1971年才发现黑洞，也就是近200年后。 从那以后，他们在太空中发现了许多黑洞。 黑洞里非常暗。 那里也有很大的重力。 黑洞的引力太大，任何东西都出不去，连光也出不去。 这就是我们看不到它们的原因。 宇宙学家通过观察黑洞周围的物体来发现黑洞。 例如，黑洞附近的恒星和气体运动得非常快。

Black holes can be very big or very small. Cosmologists believe the biggest black hole is as big as ten billion of our suns. They think there is a large black hole at the center of every galaxy. The black hole at the center of Earth's galaxy is called Sagittarius A. Cosmologists believe some black holes are as old as the universe. They think others are made when a large star dies. Our sun is a star, but when it dies, it won't become a black hole. It is not big enough. Things in space can fall into a black hole, and when they do, they can never get out. But don't worry... Earth will never fall into a black hole because there is not one close enough.

黑洞可以很大也可以很小。 宇宙学家认为，最大的黑洞有太阳的100亿个那么大。 他们认为在每个星系的中心都有一个巨大的黑洞。 位于地球星系中心的黑洞被称为人马座A。 宇宙学家认为，一些黑洞和宇宙一样古老。 他们认为其他恒星是在大恒星死亡时形成的。 我们的太阳是一颗恒星，但当它死亡时，它不会变成黑洞。 它不够大。太空中的东西可能会落入黑洞，一旦落入黑洞，它们就再也出不去了。 不过别担心……地球永远不会落入黑洞，因为没有一个足够近的黑洞。