Zero Shadow Day is a fascinating astronomical phenomenon that occurs twice a year in regions located between the Tropic of Cancer and the Tropic of Capricorn. On this day, the Sun is positioned directly overhead at noon, causing vertical objects to cast no shadow for a brief moment. It’s not an eclipse or any rare cosmic event but a direct result of Earth’s tilt and orbit. Zero Shadow Day occurs when the Sun’s declination equals the latitude of a particular place. Since the sunlight falls vertically, it does not cast a shadow on any upright object. On April 24, 2025, Bengaluru will experience ZSD at around 12:17 PM. During this brief moment, vertical objects like poles and people standing upright will cast no shadow, as the Sun will be directly overhead. This phenomenon occurs because the Sun's rays strike the Earth at a 90-degree angle, causing shadows to disappear. Venus, Saturn and Moon To Form ‘Smiley Face’ in Sky on April 25: How To Watch the Rare ‘Cosmic Emoji’ Planetary Alignment From India? Everything To Know About the Celestial Event.

Why Will There Be No Shadow Around Noon?

Zero Shadow Day results from the Earth's axial tilt and orbit around the Sun. The Earth's axis is tilted at an angle of approximately 23.5 degrees relative to its orbital plane. This tilt causes the Sun's apparent position in the sky to change throughout the year, leading to variations in the length and direction of shadows cast by objects on the Earth's surface. In regions between the Tropics of Cancer and Capricorn, the Sun can be directly overhead at certain times of the year, leading to Zero Shadow Day. New Planet On It’s Last Breath: MIT Astronomers Discover Exoplanet BD+05 4868 Ab Disintegrating Near Host Star, Leaving Behind Comet-Like Tail.

How Often Does Zero Shadow Day Occur?

In Bengaluru, this alignment occurs twice annually, allowing residents to observe the phenomenon. ​Zero Shadow Day occurs twice a year in any location situated between the Tropic of Cancer (23.5°N) and the Tropic of Capricorn (23.5°S), which is within the tropical region of the Earth. The phenomenon happens when the Sun is exactly overhead at local noon, causing upright objects to cast no shadow for a brief period.

Duration Of Zero Shadow Day In Bangalore

The duration of Zero Shadow Day is brief, typically lasting only a few minutes. In Bengaluru, it is expected to occur between 12:17 PM and 12:23 PM IST. During this time, vertical objects will cast no shadow as the Sun aligns perfectly overhead.​

Zero Shadow Day is a remarkable celestial event that offers a glimpse into the intricate movements of our planet and its relationship with the Sun. For Bengaluru residents, the upcoming event on April 24 provides an excellent opportunity to engage with science.

(The above story first appeared on LatestLY on Apr 24, 2025 07:15 AM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).