Updated: May 13, 2021 8:08:11 pm
Pune residents witnessed Zero Shadow Day virtually at 12.31 pm on Thursday.
The phenomenon of disappearing of the shadow occurs when the Sun comes exactly overhead, known as zenith, over all the regions along between the tropics — the Tropic of Cancer and the Tropic of Capricorn.
During its apparent North to South and South to North movement, there are two days in a calendar year when the Sun’s declination and the latitude of a place within the tropics align briefly, making shadows disappear momentarily.
Many astronomy clubs and groups, scientific institutions like Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pimpri-Chinchwad Science Centre, Nehru Planetarium, Mumbai and science departments at colleges host live demonstrations to show the phenomenon to school students and the public.
The event draws large crowds to these institutions as everyday objects like wristwatches, pens and measuring scales are used to explain the disappearance of the shadow. The shadows of people, too, are shown disappearing and later re-appearing.
However, there were almost no live demonstrations on Thursday due to the pandemic.
Pune-based Jyotirvidya Parisanstha (JVP), India’s oldest astronomy group hosted a livestream of the event from their Kesariwada observatory on their social media channels on Thursday.
The Zero Shadow Day was also observed over Ahmedabad, Surat, Mumbai, Nagpur and almost all of Chattisgarh and Odisha as well as parts of north Telangana.
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