Saudi Gazette report

RIYADH — The skies over Saudi Arabia and the rest of the Northern Hemisphere witnessed the summer solstice at 5:42 AM Makkah time on Saturday, June 21. At this moment, the sun came directly overhead above the Tropic of Cancer (latitude 23.5° N), marking the beginning of astronomical summer. This year, the astronomical summer will last 93 days, 15 hours, and 37 minutes.

The Jeddah Astronomical Society President Eng. Majed Abu Zahra said that on this day, the sun rises from the far northeast and sets in the far northwest. At noon, the shadows of objects are the shortest of the year, and the sun's apparent path takes its highest arc northward, placing it at its highest altitude in the sky of the year, especially in areas north of the equator.

Abu Zahra pointed out that it is important to differentiate between astronomical summer and climatic summer. Meteorologists consider summer to extend from June 1 to August 31, while in astronomy, summer begins when the sun reaches its maximum altitude, i.e., the day of the summer solstice. Although this day is the longest day of the year in terms of the number of hours of sunlight, it is not necessarily the hottest. This is because the oceans, land and atmosphere take time to absorb and store solar energy, then re-emit it. This delay in feeling the heat is known as the “seasonal lag”, and temperatures usually peak in July or August.

Abu Zahra said that the summer solstice occurs when the sun reaches its apparent northernmost point in the sky. This coincides with the Earth reaching a position in its orbit where its axis is tilted at the maximum angle (23.5 degrees) toward the sun, causing the longest day and shortest night of the year in the Northern Hemisphere, while the situation is completely reversed in the Southern Hemisphere.

"The summer solstice does not occur on the same day every year, but rather between June 20 and 22. This is due to the difference between the calendar year (365 days) and the tropical year (365.2422 days), along with the gravitational effects of the moon and planets, and the slight fluctuations in the Earth's rotation, which are compensated for by adding a leap day every four years," he said.