Zero Shadow Day (ZSD), an fascinating celestial phenomenon, happens twice in a yr, when the solar is instantly overhead and thus no shadow of any vertical object might be seen.
It occurs due to the lean of the Earth’s axis and its rotation across the solar. This tilt causes the angle of the solar rays to vary all year long, which in flip reveals numerous size and path of shadows.
The axis about which the earth rotates is tilted at an angle of 23.45 levels to the aircraft of the earth’s orbital aircraft and the solar’s equator. ZSD happens when the solar’s declination (earth’s axis leads to a every day variation of the angle between the earth–solar line and the earth’s equatorial aircraft) turns into equal to the latitude of the situation and the solar’s rays will fall precisely vertical relative to an object on the bottom resulting in no shadow of that object.
ZSD occurs twice a yr for areas between the Tropic of Cancer and the Tropic of Capricorn. The latitude of Hyderabad is 17.3850° N and it may be seen on May 9 at 12.12 p.m. and on August 3, when the shadow of any vertical object will disappear at this immediate, mentioned director of GP Birla Archaeological, Astronomical and Scientific Research Institute Ok.G. Kumar on Wednesday.
A easy experiment might be carried out at dwelling to take pleasure in this phenomenon. Arrange a flat floor which is instantly beneath the solar. Fix a white paper on the flat floor. Around midday, place a tall opaque object like a PVC pipe or a steel tumbler vertically on the white paper on the flat floor.
You will see the shadow of the item. Mark it. Now observe the shadow in interval of 5 minutes and mark them. You will discover the shadow transferring and precisely at 12.12 p.m., you will discover that the shadow of the item will disappear for a number of moments. Continue observing the shadow. Again it’s going to turn into seen, explains Dr. Kumar.
The circumference of earth can be calculated evaluating the shadow size at a distant metropolis located in the identical longitude on the identical time of ZSD in our metropolis. Subject to the climate situation and look of the solar, the ZSD occasion shall be demonstrated at B M Birla (*9*) on May 9 from 12 p.m. onwards until the no shadow interval. Those attempting at dwelling can share their photos to birlasc@gmail.com, mentioned a press launch.
