On September 22, people in Pakistan and around the world will witness the September Equinox, a rare event where day and night are almost equal in length. This occurs when the sun crosses the equator, moving from the Northern Hemisphere to the Southern Hemisphere. In Pakistan, the equinox will happen at 5:43 PM local time.

During the equinox, daylight and nighttime are nearly the same—around 12 hours each—because the sun’s rays directly hit the equator. This phenomenon, which happens twice a year in March and September, highlights the importance of the equator in the Earth’s solar path, as it divides the planet into the Northern and Southern Hemispheres.

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For those in the Northern Hemisphere, including Pakistan, the September Equinox marks the beginning of autumn, leading to shorter days and longer nights. Conversely, in the Southern Hemisphere, the equinox signals the start of spring, with warmer weather and longer days. The sun will rise exactly in the east and set precisely in the west during this event.

The equinoxes are part of the Earth’s tilt and orbit around the sun, which causes the varying lengths of days and nights throughout the year. Other key solar events include the Summer Solstice in June, the longest day of the year, and the Winter Solstice in December, the shortest day. Historically, equinoxes and solstices were crucial for tracking seasons and agriculture, and the September Equinox remains an important reminder of the Earth’s connection with the sun.