An astronomical phenomenon, ‘Zero Shadow Day', will be observed in Mangaluru on April 24 and in Udupi on April 25.

According to a press release from Poornaprajna Amateur Astronomers’ Club, the wonder will commence and people will see their shadows disappear for a few moments at 12:28 pm.

The phenomenon is called as Zero Shadow Day. If a person takes a candle in a dark room and use it to create a shadow of one’s palm on the wall, the hand will cast shadow on the wall as one moves the hand. But when one places the palm on the wall, there will be no shadow.

In the phenomenon, the sun at these times shines exactly above the heads on these days. In astronomy, this point is called as Zenith. The point in the sky directly above an observer at any given location. So it is quite clear now that on Zero Shadow Day, the sun passes through the Zenith as a result of which, all objects will have minimal or no shadow if they are on the ground.

The reason for this happens on some specific days is concerned with astronomy. The earth spins around on its own axis and causes days and nights. It also revolves around the sun causing a year. But the seasons are caused because the axis is tilted at an angle of 23.5 degrees. It is because of this tilt that the sun rises every day in the east gradually moving towards the north till June 21st and then slowly proceeding towards the south till December 21st every year. “We call these days solstice. This means the sun shines between the Tropic of Cancer and Tropic of Capricorn every day passing by the equator on the days we call equinox,” the release stated.

As the earth moves around the sun and revolves on its own axis, for all the people between Tropic of Cancer and Tropic of Capricorn, the Sun at noon moves father and closer to the zenith passing through zenith twice causing two Zero Shadow Days per year. People at Mangaluru will observe this on April 24 and August 18 every year and People in Udupi will observe this on April 25 and August 17 every year.

Places with same latitudes will observe the same days of Zero Shadow but the time would vary with longitude. For example, people of Bengaluru as they share the latitude with Mangaluru will also observe it on April 24. While the people of Mangaluru will observe their shadows disappear at 12.28pm, people of Bengaluru will observe this at 12:17pm. Places like Moodabidri, Bantwal, Sakleshpur and Hassan will also observe Zero Shadow on April 24.

Places like Brahmavar, Karkala, Sringeri, Kudremukha, Chikkamagaluru will observe the Zero Shadow Day on the same day as Udupi on April 25.