Zero Shadow Day (ZSD)
- Several districts in West Bengal, including Kolkata, Howrah, Hooghly, and others, will witness the rare astronomical phenomenon of Zero Shadow Day (ZSD) in June and July 2025.
- ZSD occurs twice a year in locations between the Tropic of Cancer and the Equator, when the Sun is exactly overhead at local noon, causing vertical objects to cast no shadow.
- The phenomenon is a result of the Sun’s declination matching the latitude of a given location, making it a direct overhead event for a brief period around solar noon.
- Though ZSD has no meteorological effect, it visually demonstrates the Earth’s axial ....
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