Earth reached its annual aphelion on Monday at 8:30 p.m. Makkah time, marking the point in its orbit farthest from the Sun at approximately 152 million kilometers. According to the Jeddah Astronomy Society and the Noor Astronomy Society, this event confirms that seasonal changes are driven by the planet’s axial tilt rather than its distance from the Sun.
Why doesn’t aphelion make the Earth colder?
Distance from the Sun is not the primary driver of temperature. Majed Abu Zahra, director of the Jeddah Astronomy Society, stated that the approximately 23.4-degree tilt of Earth’s rotational axis is what causes seasonal changes. During the Northern Hemisphere’s summer, this tilt allows solar rays to strike the region more directly, offsetting the increased distance.
Issa Al-Ghafili, President of the Noor Astronomy Society, added that the event has no effect on the intensity of solar radiation received by Earth or the succession of the seasons. He noted that the four seasons are determined by the 23.5-degree axial tilt as the planet revolves around the star.
How does the elliptical orbit affect Earth’s speed?
Earth does not travel in a perfect circle. Abu Zahra explained that the orbit is elliptical, which causes the distance from the Sun to vary by about five million kilometers throughout the year. This shape influences the speed of the planet’s travel.
According to Abu Zahra, Earth travels more slowly at aphelion. This orbital deceleration makes summer in the Northern Hemisphere slightly longer than winter. These variations provide scientists with data to better understand the long-term evolution of seasons and Earth’s climate.
What is the difference between aphelion and perihelion?
The two points represent the extremes of Earth’s elliptical path. According to Al-Ghafili, Earth reaches aphelion during the Northern Hemisphere’s summer and perihelion—its closest point to the Sun—during the winter.
| Event | Position | Typical Timing (N. Hemisphere) |
|---|---|---|
| Aphelion | Farthest (~152m km) | Summer |
| Perihelion | Closest | Winter |
How can astronomy enthusiasts use these events?
The Noor Astronomy Society encourages the public to use these annual occurrences to dispel common misconceptions about why seasons change. By studying the elliptical orbit and axial tilt, enthusiasts can deepen their understanding of planetary science and the fundamental principles governing the solar system.
Frequently Asked Questions
Does aphelion cause a drop in global temperature?
No. According to Majed Abu Zahra, the distance increase does not result in cooler temperatures because the axial tilt determines seasonal heat.
Can you see the Sun get smaller during aphelion?
While Abu Zahra noted that the Sun is technically smaller at aphelion than at perihelion, the difference is too small to be seen with the naked eye.
What causes the seasons if not the distance from the Sun?
Both the Jeddah and Noor Astronomy Societies attribute the seasons to Earth’s axial tilt (approximately 23.4 to 23.5 degrees).
Do you track annual astronomical events?
