astronomical unit

简明释义

天文单位天文单位

英英释义

例句

1.The distance from the Earth to the Sun is approximately 1 astronomical unit.

地球到太阳的距离大约是1天文单位。

2.The planet Venus is about 0.72 astronomical units away from the Sun.

金星距离太阳大约0.72天文单位。

3.One astronomical unit is about 93 million miles.

一个天文单位大约是9300万英里。

4.Astronomers use the astronomical unit as a convenient way to express distances in space.

天文学家使用天文单位作为在太空中表示距离的便利方式。

5.When measuring the distance to nearby stars, astronomers often refer to light years instead of astronomical units.

在测量到附近恒星的距离时，天文学家通常提到光年而不是天文单位。

作文

The universe is vast and complex, filled with countless celestial bodies that captivate our imagination. To comprehend the immense distances between these objects, astronomers have developed various units of measurement. One of the most important of these is the astronomical unit, a standard unit of measurement used to describe distances within our solar system. The astronomical unit (AU) is defined as the average distance from the Earth to the Sun, which is approximately 93 million miles or about 150 million kilometers.Understanding the concept of the astronomical unit is crucial for anyone interested in astronomy or space science. It provides a convenient way to express and compare the distances of planets, moons, and other celestial bodies relative to our home planet. For instance, when we say that Mars is about 1.5 AU from the Sun, it means that Mars is one and a half times farther from the Sun than Earth is. This relative measurement simplifies our understanding of the solar system's structure.The use of the astronomical unit extends beyond just our solar system. When astronomers observe distant stars and galaxies, they often use light-years as a unit of distance. However, when discussing the distances of objects within our solar system, the astronomical unit remains the preferred choice due to its practicality. For example, the distance from the Earth to Jupiter is about 5.2 AU. This means that Jupiter is over five times farther from the Sun than Earth, which helps us visualize the scale of our solar system.Moreover, the astronomical unit is not just a static measure; it has practical applications in various fields of astronomy. For instance, when planning missions to other planets, space agencies like NASA must calculate distances in AU to determine travel times and fuel requirements. A good example is the Voyager spacecraft, which traveled through the solar system, and its journey was measured in astronomical units to help scientists understand its trajectory.In addition to its use in measuring distances, the astronomical unit also plays a significant role in understanding gravitational interactions between celestial bodies. The gravitational force between two objects decreases with the square of the distance between them. By using the astronomical unit as a reference, astronomers can better understand the gravitational influences of planets on each other, which is essential for predicting planetary orbits and behaviors.In conclusion, the astronomical unit is a fundamental concept in astronomy that allows us to grasp the vastness of our solar system and beyond. It serves as a bridge between our everyday experiences and the extraordinary scales of the universe. Whether we are observing planets, planning space missions, or studying gravitational forces, the astronomical unit remains an indispensable tool in the field of astronomy. As we continue to explore the cosmos, understanding and utilizing the astronomical unit will be crucial in expanding our knowledge of the universe and its many wonders.

宇宙是广阔而复杂的，充满了无数天体，吸引着我们的想象力。为了理解这些物体之间的巨大距离，天文学家们开发了各种测量单位。其中最重要的之一是天文单位，这是一种用于描述我们太阳系内距离的标准测量单位。天文单位（AU）被定义为地球到太阳的平均距离，大约为9300万英里或约1.5亿公里。理解天文单位的概念对于任何对天文学或空间科学感兴趣的人来说都是至关重要的。它提供了一种方便的方法来表达和比较行星、卫星和其他天体与我们家园之间的距离。例如，当我们说火星距离太阳约为1.5 AU时，这意味着火星离太阳的距离是地球的1.5倍。这种相对测量简化了我们对太阳系结构的理解。天文单位的使用不仅限于我们的太阳系。当天文学家观察遥远的恒星和星系时，他们通常使用光年作为距离单位。然而，在讨论太阳系内的物体距离时，天文单位仍然是首选，因为它的实用性。例如，地球到木星的距离约为5.2 AU。这意味着木星离太阳的距离超过地球的五倍，这有助于我们可视化太阳系的规模。此外，天文单位不仅是一个静态的测量单位；它在天文学的各个领域都有实际应用。例如，在规划前往其他行星的任务时，像NASA这样的航天机构必须计算AU中的距离，以确定旅行时间和燃料需求。一个好的例子是旅行者号探测器，它穿越了太阳系，其旅程以天文单位进行测量，以帮助科学家了解其轨迹。除了在测量距离方面的应用外，天文单位在理解天体之间的引力相互作用方面也发挥着重要作用。两个物体之间的引力随着它们之间距离的平方而减小。通过使用天文单位作为参考，天文学家可以更好地理解行星之间的引力影响，这对于预测行星轨道和行为至关重要。总之，天文单位是天文学中的一个基本概念，使我们能够抓住我们太阳系及其以外的广阔。它作为我们日常经验与宇宙非凡规模之间的桥梁。无论我们是在观察行星、规划太空任务，还是研究引力作用，天文单位在天文学领域中都是不可或缺的工具。随着我们继续探索宇宙，理解和利用天文单位将对扩展我们对宇宙及其许多奇观的知识至关重要。