perihelion

简明释义

英[ˌperɪˈhiːlɪən]美[ˌperɪˈhilɪən]

n. [天] 近日点；最高点

复 数 p e r i h e l i a 或 p e r i h e l i o n s

英英释义

单词用法

同义词

反义词

例句

1.The point in the orbit nearest the sun is called perihelion, while the point farthest is called aphelion.

在轨道上最接近太阳的点被称为近日点，而最远离太阳的点被称为远日点。

2.Easy to spot in binoculars for now, McNaught will sink into the twilight along the eastern horizon in the coming days as it heads toward perihelion (closest approach to the Sun) on July 2.

现在用双筒望远镜很容易找到麦克·诺特彗星，它将在以后一段时间，在黎明东边地平线上慢慢下落，7月2日过近日点。

3.This composite neatly compares two pictures of the Sun taken with the same telescope and camera on the dates of Perihelion (closest approach) and Aphelion in 2008.

这张合成照片直观地比较了两张由同一台望远镜和照相机拍摄的太阳，一张拍摄于2008年近日点，另一个拍摄于同年的远日点。

4.This paper derives in detail the gravitational field of the sun by using the Schwarzschild metric, and expounds the advance of the Mercury's perihelion with the general theory of relativity.

用史瓦西度规详尽地推导了太阳引力场，用广义相对论解释了水星近日点的进动。

5.This paper derives in detail the gravitational field of the sun by using the Schwarzschild metric, and expounds the advance of the Mercury's perihelion with the general theory of relativity.

用史瓦西度规详尽地推导了太阳引力场，用广义相对论解释了水星近日点的进动。

6.He also figured out the planet goes faster when it's at perihelion, nearer the sun, than when it's at aphelion, its farthest distance.

他还指出了，地球在近日点的速度要比它在远日点快，近日点离太阳比较近，远日点是距离太阳最远的地方。

7.But it's not that simple either, because the dates of the perihelion and aphelion are also shifting.

但这并不是简单的一件事情，因为近日点和远日点的日期都会变换。

8.The Q is - do you mean Pluto in its aphelion or perihelion ?

我的问题是，冥王星此时是在近地点还是远地点？

9.According to Marsden's calculations, this comet reaches its closest point to the Sun (perihelion) on March 18th.

根据Marsden的计算，这颗彗星会在3月18日过近日点。

10.During the perihelion 近日点, the Sun appears slightly larger in the sky.

在perihelion 近日点期间，太阳在天空中看起来稍微大一些。

11.Scientists study the effects of perihelion 近日点 on climate patterns.

科学家研究perihelion 近日点对气候模式的影响。

12.The planet Earth reaches its perihelion 近日点 around January 3rd each year.

地球每年大约在1月3日达到它的perihelion 近日点。

13.The gravitational pull is stronger at perihelion 近日点, affecting satellite orbits.

在perihelion 近日点时，引力更强，影响卫星轨道。

14.Astronomers calculate the perihelion 近日点 of comets to predict their visibility.

天文学家计算彗星的perihelion 近日点以预测它们的可见性。

作文

The concept of perihelion is fundamental in understanding the dynamics of celestial bodies within our solar system. The term perihelion refers to the point in the orbit of an object where it is closest to the Sun. This term is derived from the Greek words 'peri', meaning 'near', and 'helios', meaning 'sun'. The significance of perihelion can be observed not only in the context of Earth’s orbit but also in the orbits of other planets, comets, and asteroids. Understanding perihelion helps us comprehend various phenomena related to gravitational forces, orbital mechanics, and seasonal changes on Earth.Every year, Earth reaches its perihelion around early January. At this time, our planet is approximately 147 million kilometers away from the Sun, which is about 3 million kilometers closer than its farthest point, known as aphelion. Despite being closer to the Sun during perihelion, many people mistakenly believe that this proximity is responsible for warmer temperatures. However, the seasons are primarily determined by the tilt of the Earth's axis rather than its distance from the Sun.The study of perihelion is not limited to Earth. For instance, the planet Mercury experiences its perihelion much more dramatically due to its highly elliptical orbit. As Mercury approaches its perihelion, it speeds up significantly, illustrating Kepler's laws of planetary motion. These laws describe how planets move in elliptical orbits with varying speeds depending on their distance from the Sun. This phenomenon is a perfect example of how perihelion affects the velocity of a planet in its orbit.Moreover, comets exhibit fascinating behaviors related to their perihelion. When a comet approaches the Sun, it heats up and begins to release gas and dust, creating a glowing coma and tail. The perihelion of a comet is often the most visually spectacular part of its journey, as the interaction with solar radiation leads to dramatic changes in its appearance. Observing these events provides valuable insights into the composition of comets and the early solar system.In addition to its astronomical implications, the concept of perihelion has inspired various cultural and scientific discussions. For example, the timing of Earth’s perihelion has been linked to ancient agricultural practices, influencing planting and harvesting schedules. Furthermore, understanding the perihelion and its effects on climate patterns can contribute to climate science, helping researchers predict future weather trends and ecological changes.In conclusion, the term perihelion encapsulates a crucial aspect of celestial mechanics that extends beyond mere definitions. It represents a point of interest for astronomers, scientists, and enthusiasts alike. By studying perihelion, we gain deeper insights into the behavior of celestial bodies, the nature of our solar system, and even the broader universe. As we continue to explore the cosmos, the knowledge of perihelion will undoubtedly play a significant role in our quest to understand the intricate dance of the stars and planets.

“近日点”这一概念在理解我们太阳系内天体的动态方面至关重要。术语“近日点”指的是一个物体在其轨道上离太阳最近的点。这个词源于希腊语中的“peri”，意为“近”，以及“helios”，意为“太阳”。“近日点”的重要性不仅可以在地球的轨道上下文中观察到，还可以在其他行星、彗星和小行星的轨道中看到。理解“近日点”有助于我们理解与引力、轨道力学和地球季节变化相关的各种现象。每年，地球在一月初达到其“近日点”。此时，我们的星球距离太阳大约147百万公里，比其最远点（称为远日点）近约300万公里。尽管在“近日点”期间离太阳更近，但许多人错误地认为这种接近是温暖气温的原因。然而，季节主要由地球轴的倾斜决定，而不是地球与太阳之间的距离。“近日点”的研究并不限于地球。例如，水星由于其高度椭圆的轨道而经历更为戏剧性的“近日点”。当水星接近其“近日点”时，它的速度显著加快，展示了开普勒的行星运动定律。这些定律描述了行星如何以椭圆轨道运动，且根据它们与太阳的距离以不同的速度运动。这一现象是“近日点”如何影响行星轨道速度的完美例证。此外，彗星在与其“近日点”相关的行为上也表现出迷人的特征。当彗星接近太阳时，它会加热并开始释放气体和尘埃，形成发光的彗发和尾巴。彗星的“近日点”通常是其旅程中视觉上最壮观的部分，因为与太阳辐射的相互作用导致其外观发生戏剧性变化。观察这些事件为我们提供了关于彗星成分和早期太阳系的宝贵见解。除了天文学的影响外，“近日点”这一概念还激发了各种文化和科学讨论。例如，地球“近日点”的时机与古代农业实践有关，影响着种植和收获的时间。此外，理解“近日点”及其对气候模式的影响可以为气候科学做出贡献，帮助研究人员预测未来的天气趋势和生态变化。总之，术语“近日点”概括了一个关键的天体力学方面，超越了简单的定义。它代表了天文学家、科学家和爱好者共同关注的兴趣点。通过研究“近日点”，我们对天体的行为、我们的太阳系的性质甚至更广阔的宇宙获得了更深刻的见解。随着我们继续探索宇宙，“近日点”的知识无疑将在我们理解星星和行星的复杂舞蹈的过程中发挥重要作用。