Zero shadow at 12.17 pm today

By NT Correspondent

Bengaluru: The city is set to witness an astronomical phenomenon called ‘Zero Shadow Day’ on Sunday when the Sun reaches exactly overhead.

At 12.17 pm, the shadow of vertical objects will disappear in Bengaluru. The phenomenon occurs at all places on the 13 degrees North latitude, including Chennai and Mangaluru, but at a different time at each location.

The Jawaharlal Nehru Planetarium in the city has scheduled several demonstrations for the general public as well as students participating in its workshop. Planetarium Director Pramod G Galgali told News Trail that a 3-metre-long vertical pole would be used to demonstrate zero-shadow occurrence.

Along with this, a Sun-themed poster exhibition has been planned. “A Solar-scope will be set up which will enable visitors to get a glimpse of sun spots,” the Director said.

The students participating in the Zero Shadow Day workshop will calculate the Earth’s circumference using a method which is about 2,000 years old.

The planetarium is organising educational events in association with other planetaria and science centres. The Director said that children will also measure the Earth’s circumference using the angle of the shadow at Bhopal and the aerial distance between Bhopal and Bengaluru (which will have zero shadow).

The pan-India activity is said to involve students in various science centres including those from Karwar, Dharwad and Raichur.