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The Sun at the same time every day for a year ☀️

220,229 次观看 • 1 年前 •via X (Twitter)

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Jakub 的头像
Jakub1 年前

The analemma of the Sun is a figure-eight shape that results from the Earth's **tilted axis** and its **elliptical orbit** around the Sun. Here are some key points to understand it: - **Shape**: If you were to take a photograph of the Sun from the same location at the same time every day for a year, you would notice that the Sun's position in the sky describes a figure-eight path. This shape is the analemma. - **Causes**: - **Earth's Axial Tilt**: The Earth is tilted at about 23.5 degrees relative to its orbital plane. This tilt means that the Sun's declination (its angular distance north or south of the celestial equator) changes throughout the year, causing part of the analemma's vertical spread. - **Elliptical Orbit**: Earth's orbit around the Sun is not a perfect circle but an ellipse. According to Kepler's laws of planetary motion, Earth moves faster when it's closer to the Sun (perihelion, in early January) and slower when it's farther away (aphelion, in early July). This variation in speed affects the Sun's apparent position in the sky, contributing to the east-west component of the analemma. - **Equation of Time**: The analemma also reflects the **equation of time**, which is the discrepancy between "solar time" (time as indicated by the Sun's position) and **mean solar time** (the time as measured by a clock running at a uniform rate). This discrepancy arises because solar time does not run at a constant rate due to the elliptical orbit and axial tilt. - **Observation**: - From the Northern Hemisphere, the analemma will have its lower loop larger than the upper one. If observed from the Southern Hemisphere, this would be reversed, with the upper loop being larger. - At the equinoxes, the Sun is at the crossing point of the figure-eight, but due to the equation of time, it's not exactly at the center. - **Utility**: - The analemma can be used to determine the location of the Sun in the sky at any given time of year for precise solar tracking or for adjusting sundials to mean time. - **Photography**: To capture an analemma, one needs patience since it requires a year-long commitment, taking images at the same time each day, ideally with a fixed camera setup to ensure each photo aligns perfectly. The analemma is not only a beautiful celestial pattern but also a practical diagram for understanding the Sun's yearly journey across our sky, demonstrating the complex interplay between Earth's rotation, tilt, and orbit. Wisdom by grok.

Decoding Engineering 的头像
Decoding Engineering1 年前

This is called Analemma! An analemma is a figure-8 shaped diagram showing the position of the Sun in the sky, as seen from a fixed location on Earth at the same mean solar time, throughout the year. It is created due to: 1. The Earth's axis is tilted at approximately 23.5°, causing the Sun's position to vary in the sky throughout the year. 2. The Earth's orbit around the Sun is not a perfect circle, it's slightly elliptical. This causes the Earth's distance from the Sun to vary. The analemma's shape is unique to Earth. Other planets have their own analemmas based on their tilt and orbital characteristics.

Sundar 的头像
Sundar1 年前

Infinity Symbol. Beginning is end, end is beginning

समीर .🌼 的头像
समीर .🌼1 年前

This...

Rahul Meena 的头像
Rahul Meena1 年前

Sun 🌞🌞

Alan C Bruce-Author 的头像
Alan C Bruce-Author1 年前

Its an amazing

Atiswan Goel 的头像
Atiswan Goel1 年前

and that's infinity for you

Andreas Koll 🇦🇹 的头像
Andreas Koll 🇦🇹1 年前

Which location is that?

Antima Singh🇮🇳🌿 的头像
Antima Singh🇮🇳🌿1 年前

Stop November 🏝️🏝️🌸🕉️

Statistic Mania 的头像
Statistic Mania1 年前

Average temperature of the planets in our solar system 🪐 : Mercury: 333°F (167°C) Venus: 867°F (464°C) Earth: 59°F (15°C) Mars: -85°F (-65°C) Jupiter: -166°F (-110°C) Saturn: -220°F (-140°C) Uranus: -320°F (-195°C) Neptune: -330°F (-200°C)

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