At precisely 12:17 PM on April 24, Bengaluru will witness the fascinating Zero Shadow Day—a moment when the Sun is directly overhead and upright objects cast no visible shadow. This unique celestial event, confirmed by scientists at the Indian Institute of Astrophysics (IIA), occurs twice a year in places located south of the Tropic of Cancer.

Dr. Niruj Mohan Ramanujam, head of IIA’s science outreach division, explains that this phenomenon happens when the Sun is at its zenith, causing shadows to fall directly underneath objects—making them effectively disappear for a brief moment.

In Bengaluru, this spectacle typically occurs around April 24–25 and again on August 18. Other cities like Chennai and Mangaluru also experience it, since they lie below the Tropic of Cancer.

Ramanujam noted that Zero Shadow Day will touch the Tropic of Cancer itself on June 21, coinciding with the summer solstice—the longest day of the year and the conclusion of Uttarayana, the sun’s northward journey in the Hindu calendar.

So step outside at noon on April 24 and watch your shadow disappear—science doesn’t get cooler than this.