hour circle

简明释义

时圈

英英释义

例句

1.The astronomer used the hour circle to measure the position of stars in the night sky.

天文学家使用时圈来测量夜空中星星的位置。

2.The hour circle is essential for tracking the movement of celestial bodies.

时圈对于追踪天体的运动至关重要。

3.Using the hour circle, sailors can determine their longitude at sea.

水手可以使用时圈来确定他们在海上的经度。

4.During the lecture, the professor explained how the hour circle relates to right ascension.

在讲座中，教授解释了时圈如何与赤经相关。

5.To find the celestial coordinates, we need to align the telescope with the hour circle.

为了找到天体坐标，我们需要将望远镜与时圈对齐。

作文

The concept of the hour circle is fundamental in the field of astronomy. An hour circle is defined as a great circle on the celestial sphere that passes through both the celestial poles and the observer's zenith. This term is essential for understanding how celestial objects move across the sky and how we can measure time based on their positions. In essence, the hour circle helps astronomers and navigators determine the local sidereal time, which is crucial for tracking the movement of stars and planets.When we look up at the night sky, we see countless stars, but they are not static. They move across our field of vision due to the rotation of the Earth. The hour circle provides a framework for understanding this motion. Each star has its own hour circle, which corresponds to its position in the sky. As the Earth rotates, different stars rise and set, and the hour circle allows us to predict when these events will occur.For instance, consider the North Star, Polaris. Its hour circle runs very close to the North Celestial Pole, making it an excellent reference point for navigation. Sailors and travelers have relied on the constancy of Polaris to guide them for centuries. By understanding the position of Polaris in relation to the hour circle, navigators can determine their latitude and make informed decisions about their journey.Moreover, the hour circle is also linked to the concept of right ascension, which is one of the two coordinates used in the equatorial coordinate system. Right ascension measures the angle along the celestial equator from the vernal equinox to the hour circle of a celestial object. This means that every star's position can be described in terms of its hour circle and declination, allowing astronomers to locate it accurately in the sky.In practical applications, the hour circle is utilized in various astronomical instruments, such as telescopes and star charts. Observers use these tools to track the movements of celestial bodies and to predict events like eclipses or transits. Understanding the hour circle enhances our ability to appreciate the beauty of the cosmos and the intricate dance of celestial mechanics.In conclusion, the hour circle is more than just a technical term; it represents a vital aspect of our understanding of the universe. By grasping the significance of the hour circle, we can better appreciate the movements of stars and planets, navigate our world, and explore the mysteries of the cosmos. As we continue to study the heavens, the hour circle will remain a key component in our quest for knowledge about the universe and our place within it.

“小时圈”这一概念在天文学领域中是基础的。“小时圈”被定义为一个经过天球的两个极点和观察者的天顶的大圆圈。这个术语对于理解天体如何在天空中移动以及我们如何根据它们的位置来测量时间至关重要。从本质上讲，“小时圈”帮助天文学家和导航员确定地方恒星时，这对于追踪星星和行星的运动至关重要。当我们仰望夜空时，会看到无数的星星，但它们并不是静止的。由于地球的自转，它们在我们的视野中移动。“小时圈”为理解这种运动提供了框架。每颗星星都有自己的“小时圈”，与其在天空中的位置相对应。随着地球的旋转，不同的星星升起和落下，而“小时圈”使我们能够预测这些事件何时发生。例如，考虑北极星，北极星的“小时圈”非常接近北天极，使其成为导航的优秀参考点。航海者和旅行者依靠北极星的恒定性来指导他们的方向已有几个世纪。通过理解北极星与“小时圈”的位置关系，导航员可以确定他们的纬度，并对他们的旅程做出明智的决定。此外，“小时圈”还与赤经的概念相关，赤经是赤道坐标系统中用于描述天体位置的两个坐标之一。赤经测量从春分点到天体的“小时圈”的角度。这意味着每颗星星的位置都可以用其“小时圈”和赤纬来描述，从而使天文学家能够准确地定位它。在实际应用中，“小时圈”被用于各种天文仪器，如望远镜和星图。观察者使用这些工具来跟踪天体的运动，并预测日食或过境等事件。理解“小时圈”增强了我们欣赏宇宙之美和天体力学复杂舞蹈的能力。总之，“小时圈”不仅仅是一个技术术语；它代表了我们理解宇宙的一个重要方面。通过掌握“小时圈”的意义，我们可以更好地欣赏星星和行星的运动，导航我们的世界，并探索宇宙的奥秘。随着我们继续研究天际，“小时圈”将始终是我们探索知识、了解宇宙及其在我们心目中的位置的重要组成部分。