“Twinkle Twinkle Little Star” is a popular song for children. But have you ever wondered why the stars twinkle? I’m afraid many adults don’t understand this question, let’s unlock the mystery of the stars!
When we look up to the sky on a clear, dark night, our eyes can see about 6,000 stars in the sky. Some stars look like they are always twinkling and winkling. They are very beautiful. In fact, most of the stars are shining with a steady (稳定的) light. Not all stars twinkle. The stars that twinkle are generally stars. In addition to the Sun, the nearest star to the Earth, the neighboring star (比邻星), is also more than 4 light years away from Earth. Because the distance is too far, the stars we see are only a small point. Also, from the distant star travels a long way through the atmosphere (大气) down to us on Earth. At the same time, air is moving in the atmosphere of Earth. The movement of air causes the starlight to get slightly bent. To our eyes, this makes the star to twinkle. You will notice that stars closer to the horizon appear to twinkle more than other stars. This is because there is more atmosphere between you and a star near the horizon. However, there is no atmosphere in space to make the stars seem to twinkle. That’s why the Hubble telescope (哈勃望远镜), which is in space, can take such clear pictures of other galaxies (星系).
Go out tonight and take a look at the stars twinkling in the sky!
【小题1】On a clear, dark night, our eyes can see _________ stars in the sky.
| A．less than 6,000 | B．around 6,000 | C．more than 6,000 | D．Not mentioned in the article |
【小题2】According to the article, most stars are shining with a light __________.
| A．bright | B．colourful | C．fixed | D．flashing |
【小题3】What makes stars seem to twinkle?
| A．The movement of air in the atmosphere of Earth. |
| B．Air on Earth. |
| C．The long distance between stars and Earth. |
| D．The movement of stars. |
【小题4】Why can the Hubble telescope take clear pictures of other galaxies?
| A．Because stars twinkle in space. | B．Because air is not moving in space. |
| C．Because the telescope is close to stars. | D．Because there is no atmosphere in space. |
【小题5】Which is the best title of this passage?
| A．Why are many stars so dim at night? | B．Which song do children like best? |
| C．How to observe the stars from Earth? | D．What do stars look like? |
