light year

简明释义

光年

英英释义

例句

1.The Andromeda Galaxy is approximately 2.537 million light years (光年) away from Earth.

仙女座星系距离地球大约253.7万光年（光年）。

2.The nearest star to Earth, Proxima Centauri, is about 4.24 light years (光年) away.

离地球最近的星星比邻星大约在4.24光年（光年）之外。

3.Astronomers use light years (光年) as a unit of measurement to express distances in space.

天文学家使用光年（光年）作为单位来表示太空中的距离。

4.When we say a galaxy is 10 million light years (光年) away, it means the light we see from it took 10 million years to reach us.

当我们说一个星系距离我们有1000万光年（光年）时，意味着我们看到的光花了1000万年才到达我们这里。

5.It takes about 8.3 light years (光年) for light from Sirius to reach us.

从天狼星发出的光大约需要8.3光年（光年）才能到达我们。

作文

Understanding the concept of a light year is essential for anyone interested in astronomy and the vastness of the universe. A light year is not a measure of time, but rather a measure of distance. It defines how far light travels in one year. Since light moves at an incredible speed of approximately 299,792 kilometers per second (or about 186,282 miles per second), it covers an astonishing distance in just one year. This distance amounts to about 9.46 trillion kilometers (or about 5.88 trillion miles). To put this into perspective, our closest star system, Alpha Centauri, is about 4.37 light years away from Earth. This means that the light we see from Alpha Centauri today actually left the star over four years ago. Therefore, when we observe distant stars and galaxies, we are looking back in time. The farther away an object is, the older the light we see from it. For instance, if a galaxy is 100 million light years away, the light we observe today shows us what that galaxy looked like 100 million years ago. The concept of a light year helps astronomers understand the scale of the universe. The Milky Way galaxy, which is our home galaxy, is about 100,000 light years in diameter. This immense size illustrates just how vast space is and how small we are in comparison. When discussing distances in space, using light years allows scientists to convey enormous distances more easily than using kilometers or miles.In addition to its significance in astronomy, the term light year has also entered popular culture and language. People often use it metaphorically to describe significant differences or advancements. For example, someone might say, "In terms of technology, we are light years ahead of where we were a decade ago." This figurative use emphasizes the idea of being far ahead or advanced, similar to the literal meaning of light years in measuring distance in space.Moreover, understanding light years can inspire a sense of wonder about the universe. It encourages us to ponder our existence and the mysteries beyond our planet. The fact that we are part of a universe so vast that it takes light years for us to connect with other celestial bodies can be both humbling and awe-inspiring. In conclusion, the term light year is a crucial concept in both scientific and everyday contexts. Its role in measuring astronomical distances allows us to comprehend the enormity of the universe while also providing a metaphorical framework for discussing progress and advancement in various aspects of life. As we continue to explore and learn about the cosmos, the light year will remain a fundamental unit of measurement, bridging the gap between our world and the infinite universe beyond.

理解光年的概念对于任何对天文学和宇宙浩瀚感兴趣的人来说都是至关重要的。光年不是时间的度量，而是距离的度量。它定义了光在一年内传播的距离。由于光以大约每秒299,792公里（或约186,282英里）的惊人速度移动，因此它在一年内覆盖了令人震惊的距离。这一距离约为9.46万亿公里（或约5.88万亿英里）。为了更好地理解这一点，我们最近的恒星系统——阿尔法·半人马星系，距离地球约4.37光年。这意味着我们今天看到的来自阿尔法·半人马星的光实际上是在四年前离开了那颗星。因此，当我们观察遥远的星星和星系时，我们实际上是在回顾过去。物体距离越远，我们看到的光越古老。例如，如果一个星系距离我们100百万光年，那么我们今天观察到的光展示了那个星系1亿年前的样子。光年的概念帮助天文学家理解宇宙的规模。我们的银河系——即我们的家园星系，直径约为100,000光年。这个巨大的尺寸说明了太空是多么广阔，以及我们与之相比是多么渺小。在讨论宇宙中的距离时，使用光年使科学家能够比使用公里或英里更轻松地传达巨大的距离。除了在天文学中的重要性，光年这一术语也进入了流行文化和语言。人们常常用它来比喻显著的差异或进步。例如，有人可能会说：“在技术方面，我们比十年前先进了光年。”这种比喻的使用强调了远远领先或先进的概念，类似于在测量宇宙空间距离时光年的字面意义。此外，理解光年可以激发我们对宇宙的敬畏感。它鼓励我们思考自己的存在以及我们星球之外的奥秘。事实上，我们是一个如此浩瀚的宇宙的一部分，以至于光年需要时间才能与其他天体连接，这既让人谦卑又令人惊叹。总之，光年这个术语在科学和日常语境中都是一个至关重要的概念。它在测量天文距离方面的作用使我们能够理解宇宙的巨大，同时也为讨论生活各个方面的进步和发展提供了一个隐喻框架。随着我们继续探索和学习宇宙，光年将始终是一个基本的测量单位，架起我们世界与无尽宇宙之间的桥梁。