astronomical unit

简明释义

天文单位天文单位天文单位

英英释义

例句

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

地球到太阳的距离大约是一个天文单位。

2.When studying exoplanets, scientists may express their distances in astronomical units.

在研究系外行星时，科学家可能会用天文单位来表示它们的距离。

3.In astronomy, distances between stars are often measured in astronomical units.

在天文学中，星星之间的距离通常用天文单位来测量。

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

金星距离太阳大约0.72个天文单位。

5.The orbit of Mars is about 1.52 astronomical units from the Sun.

火星的轨道距离太阳大约1.52个天文单位。

作文

The universe is vast and filled with wonders that often leave us in awe. One of the fundamental concepts in astronomy is the astronomical unit, which is a standard measurement used to describe distances within our solar system. An astronomical unit (AU) is defined as the average distance from the Earth to the Sun, approximately 93 million miles or about 150 million kilometers. This unit provides a convenient way to express and compare distances between celestial bodies without resorting to cumbersome numbers. For instance, when we consider the distance from the Earth to Mars, which varies due to their elliptical orbits, it can be expressed in astronomical units. At its closest approach, Mars is about 0.52 AU from Earth, while at its farthest point, it can be about 2.5 AU away. This variability highlights the importance of using astronomical units when discussing interplanetary distances, as it simplifies our understanding of the vast spaces involved.Moreover, the astronomical unit is not just limited to measuring distances within our solar system; it also serves as a baseline for calculating distances to other stars and galaxies. For example, the nearest star system, Alpha Centauri, is approximately 4.37 light years away, which translates to about 278,000 AU. This illustrates how even the closest stars are incredibly far away, emphasizing the enormity of the universe.In addition to practical applications, the astronomical unit has historical significance. The concept of measuring distances in space dates back centuries, but it was not until the 19th century that astronomers began using the astronomical unit as a standardized measure. The development of this unit allowed for more accurate calculations and a better understanding of the solar system's structure. Understanding the astronomical unit is crucial for anyone interested in astronomy or space exploration. It helps frame our perspective on the distances involved when we discuss missions to other planets or the search for extraterrestrial life. For instance, NASA’s Mars rovers operate within a range of distances that can be expressed in astronomical units, making it easier for scientists to communicate their findings and objectives.In conclusion, the astronomical unit is an essential concept in the field of astronomy. It not only simplifies complex calculations regarding distances in our solar system but also connects us to the broader universe. As we continue to explore and learn more about space, the astronomical unit will remain a vital tool in our quest for knowledge. Understanding this measurement allows us to appreciate the scale of the cosmos and our place within it, reminding us of the beauty and complexity of the universe we inhabit.

宇宙浩瀚，充满了令人惊叹的奇观，常常让我们感到敬畏。天文学中的一个基本概念是天文单位，这是一个用于描述我们太阳系内距离的标准测量单位。天文单位（AU）被定义为地球与太阳之间的平均距离，大约为9300万英里或约1.5亿公里。这个单位提供了一种方便的方式来表达和比较天体之间的距离，而不必使用繁琐的数字。例如，当我们考虑地球与火星之间的距离时，由于它们的椭圆轨道，这个距离会有所变化，可以用天文单位来表示。在最近的接近时，火星距离地球大约0.52 AU，而在最远点，它可能远达2.5 AU。这种变异性突显了在讨论行星间距离时使用天文单位的重要性，因为它简化了我们对涉及的广阔空间的理解。此外，天文单位不仅限于测量我们太阳系内的距离；它也作为计算其他恒星和星系距离的基准。例如，离我们最近的恒星系统——阿尔法·半人马星，距离我们大约4.37光年，这大约相当于278,000 AU。这说明即使是最近的恒星也远得惊人，强调了宇宙的庞大。除了实际应用外，天文单位还有历史意义。测量太空距离的概念可以追溯到几个世纪以前，但直到19世纪，天文学家才开始使用天文单位作为标准化的测量单位。这个单位的发展使得更准确的计算成为可能，并且更好地理解了太阳系的结构。理解天文单位对于任何对天文学或太空探索感兴趣的人来说都是至关重要的。它有助于我们在讨论其他行星的任务或寻找外星生命时框定我们的视角。例如，NASA的火星探测器在一个可以用天文单位表示的距离范围内运行，使科学家能够更容易地传达他们的发现和目标。总之，天文单位是天文学领域的一个重要概念。它不仅简化了关于我们太阳系内距离的复杂计算，而且将我们与更广阔的宇宙联系起来。随着我们继续探索和学习更多关于太空的知识，天文单位将继续作为我们追求知识的重要工具。理解这个测量单位使我们能够欣赏宇宙的规模以及我们在其中的位置，提醒我们所居住的宇宙的美丽和复杂性。