Zero Shadow Day 2023, Bengaluru: What does it mean? History, meaning and significance

Zero Shadow Day 2023, Bengaluru: What does it mean? History, meaning and significance

Zero Shadow Day 2023, Bengaluru: Bengaluru will experience a rare celestial phenomenon known as "Zero Shadow Day" today i.e. April 25, in which none of the city's vertical objects would cast a shadow for a short period of time. The Indian Institute of Astrophysics (IIA) at Koramangala, Bengaluru, will host a number of events on its campus to mark this historic day.

Zero Shadow Day: Day and time

Zero Shadow Day will be observes on April 25 at 12.17 PM.

Zero Shadow Day: Where

This time, Zero Shadow Day will be observed in Bengaluru. In 2021, Odisha's Bhubaneswar witnessed a Zero Shadow Day.

Zero Shadow Day: Meaning

A unique celestial phenomenon known as a 'zero shadow day' occurs twice a year at locations between +23.5 and -23.5 degrees latitude. When the sun is at its greatest position in the sky during this time, neither live creatures nor inanimate objects cast any shadows. When the Sun is precisely at the zenith point, the Astronomical Society of India (ASI) states that it will not throw a shadow on an object.

"For people living between +23.5 and -23.5 degrees latitude, the Sun's declination will be equal to their latitude twice - once during Uttarayan and once during Dakshinayan. On these two days, the Sun will be exactly overhead at noon and will not cast a shadow of an object on the ground," as per ASI website.

When the Sun's declination matches the location's latitude, this phenomenon takes place. Even though it just lasts for a moment, the impact can be felt for up to two minutes.

Zero Shadow Day: Duration 

The actual phenomenon only lasts for a second but its effects can be seen for up to 1.5 minutes.