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Shkruar nga Pamfleti
On Monday, July 6, the Earth will reach aphelion, the point in its orbit that is furthest from the Sun. This is an astronomical phenomenon that occurs every year. This year, the distance between the Earth and the Sun will reach 152,087,774 kilometers.
It is often mistakenly believed that the seasons depend directly on the distance of the Earth from the Sun and that summer coincides with the shortest distance. In fact, aphelion proves the opposite: during the period when the Northern Hemisphere experiences the hottest days of the year, the Earth is at the furthest point in its orbit.
The cause of the change of seasons is the tilt of the Earth's axis, about 23 degrees relative to the plane of its orbit. This tilt determines the angle at which the Sun's rays fall on the planet's surface as the Earth moves around the Sun.
The Earth's orbit is not a perfect circle, but an ellipse, as described by astronomer Johannes Kepler. For this reason, the distance between the Earth and the Sun varies by about 5 million kilometers during the year.
The closest point to the Sun is called perihelion and occurs in early January, when the Earth is about 147 million kilometers away. The farthest point is called aphelion and occurs in early July.
Although this difference seems large, the difference in the amount of solar radiation that the Earth receives does not exceed 7 percent.
In July, the Northern Hemisphere is tilted toward the Sun, so the rays fall more perpendicularly on the surface and the lighting lasts longer during the day. As a result, more thermal energy accumulates, creating summer conditions, despite the Earth being at the greatest distance from the Sun.
Meanwhile, in the Southern Hemisphere, the Sun's rays fall at a greater angle and the days are shorter, which brings winter conditions.
According to the laws of celestial mechanics, the Earth moves more slowly in its orbit when it is at aphelion. For this reason, astronomical summer in the Northern Hemisphere lasts about five days longer than summer in the Southern Hemisphere.
Lini një Përgjigje