Since the sun was directly overhead at the moment, many cities in India are enjoying Zero Shadow Day.
What exactly is Zero Shadow Day?
- The occurrence of Zero Shadow Day occurs twice a year at every point on Earth between the Tropics of Cancer and Capricorn.
- Vertical objects appear to cast no shadow at local noon, when the sun is at its zenith exactly above the object, on Zero Shadow Day.
- When the sun swings from 23.5°N to 23.5°S of the Earth’s equator and back, the shadow disappears beneath objects around local noon.
What causes this to happen?
- It is caused by the sun’s journey from south to north during Uttarayan and back from north to south during Dakshinayan.
- The Earth’s rotation axis is tilted at an angle of around 23.5° to the axis of revolution around the sun, causing this movement.
- On that day, all locations whose latitude equals the angle between the location of the sun and the equator enjoy Zero Shadow Day, with the shadow dissipating at local noon.
Source: https://indianexpress.com/article/explained/explained-sci-tech/bengaluru-zero-shadow-day-what-is-it-why-does-it-happen-8575725/#:~:text=At%2012%3A17%20pm%20on,was%20directly%20under%20the%20object.