local hour angle

简明释义

地方时角

英英释义

例句

1.Astronomers often plot the local hour angle against declination to create star charts.

天文学家常常将地方时角与赤纬绘制在一起以创建星图。

2.The calculation of the sun's position requires knowing the local hour angle, which refers to the angle between the observer's meridian and the meridian containing the sun.

计算太阳位置需要知道地方时角，它指的是观察者的子午线与包含太阳的子午线之间的角度。

3.In astronomy, the local hour angle is crucial for determining the altitude and azimuth of celestial bodies.

在天文学中，地方时角对确定天体的高度和方位至关重要。

4.Navigators use the local hour angle to adjust their course based on the position of the stars.

航海家利用地方时角根据星星的位置调整航向。

5.To find the time of sunset, you can calculate the local hour angle at which the sun reaches the horizon.

要找到日落时间，可以计算太阳达到地平线时的地方时角。

作文

The concept of local hour angle is fundamental in the field of astronomy and navigation. It refers to the angle that represents the time since a celestial object has crossed the local meridian, expressed in angular measurement. Understanding this concept allows astronomers and navigators to determine the position of celestial bodies in the sky at any given moment. The local hour angle is measured in degrees, with 360 degrees representing a full rotation of the Earth. Each hour corresponds to 15 degrees, as the Earth rotates 360 degrees in approximately 24 hours. To grasp the significance of the local hour angle, one must first understand its relationship with time. When a star is directly overhead at the local meridian, its local hour angle is zero degrees. As time progresses, this angle increases; for example, after one hour, the angle would be 15 degrees, indicating that the star has moved westward from the meridian. This movement continues until the star sets below the horizon, at which point the local hour angle reaches 180 degrees.Astronomers use the local hour angle to calculate the altitude and azimuth of stars and planets. The altitude is the angle above the horizon, while the azimuth is the angle measured clockwise from the north. By knowing the local hour angle and the declination of the celestial object (the angle between the object and the celestial equator), astronomers can apply trigonometric formulas to find the object's position in the sky. In practical applications, such as celestial navigation, sailors rely on the local hour angle to determine their position at sea. By observing the angles of celestial bodies at specific times, they can calculate their latitude and longitude. This method was historically significant before the advent of modern GPS technology. Furthermore, the local hour angle plays a crucial role in the design and functioning of telescopes. Astronomers must adjust their instruments according to the local hour angle to track celestial objects accurately. Without this adjustment, the objects would appear to drift out of view due to the Earth's rotation. In conclusion, the local hour angle is an essential concept that bridges the gap between time and celestial positioning. Its application spans across various fields, including astronomy, navigation, and even the operation of telescopes. By understanding the local hour angle, one gains insight into the dynamic movements of celestial bodies and their relationship with our planet. This knowledge not only enriches our understanding of the universe but also enhances our ability to navigate and explore the world around us.

“地方时角”这一概念在天文学和导航领域中至关重要。它指的是一个角度，表示某个天体越过当地子午线以来的时间，以角度测量表示。理解这一概念使天文学家和导航员能够确定任何给定时刻天空中天体的位置。“地方时角”以度数为单位进行测量，360度代表地球的完整旋转。每小时对应15度，因为地球在大约24小时内旋转360度。要理解“地方时角”的重要性，首先必须了解它与时间的关系。当一颗星星正好在当地子午线上方时，它的“地方时角”为零度。随着时间的推移，这个角度会增加；例如，经过一个小时后，角度将为15度，表明星星已经向西移动。这个运动会持续，直到星星落到地平线以下，此时“地方时角”达到180度。天文学家使用“地方时角”来计算星星和行星的高度和方位。高度是指天体在地平线上的角度，而方位是从北方顺时针测量的角度。通过知道“地方时角”和天体的赤纬（天体与天球赤道之间的角度），天文学家可以应用三角函数公式来找到天体在天空中的位置。在实际应用中，例如天文导航，水手依靠“地方时角”来确定他们在海上的位置。通过观察特定时间天体的角度，他们可以计算出自己的纬度和经度。在现代GPS技术出现之前，这种方法具有历史意义。此外，“地方时角”在望远镜的设计和操作中也发挥着关键作用。天文学家必须根据“地方时角”调整他们的仪器，以准确追踪天体。如果没有这种调整，天体会因地球的自转而看起来漂移出视野。总之，“地方时角”是一个重要的概念，连接了时间和天体定位之间的联系。它的应用跨越了多个领域，包括天文学、导航，甚至望远镜的操作。通过理解“地方时角”，人们可以深入了解天体的动态运动及其与我们星球的关系。这一知识不仅丰富了我们对宇宙的理解，还增强了我们导航和探索周围世界的能力。