Zero Shadow Day is a phenomenon that occurs twice a year
On Tuesday, Hyderabad witnessed a unique celestial event "Zero Shadow Day" at 12:12 pm. This event occurs when the sun's position is directly overhead and casts no shadow on vertical objects. Several Hyderabad residents posted videos and pictures on their social media handles when there was no shadow from sunlight.
Zero Shadow Day is a phenomenon that occurs twice a year, where the Sun's position is directly overhead, casting no shadows on the Earth's surface.
See the post here:
During Zero Shadow Day, the sun reaches its highest point in the sky resulting in the reduction of the length of the shadow. When we stand on this shadow, our own shadow becomes invisible, hence the term "Zero Shadow".
"For people living between +23.5 and -23.5 degrees latitude, the Sun's declination will be equal to their latitude twice - once during Uttarayan and once during Dakshinayan. On these two days, the Sun will be exactly overhead at noon and will not cast a shadow of an object on the ground," the Astronomical Society of India noted.
Explaining the phenomenon, astrophysicist Debiprosad Duari told PTI, "People and any object, all around the world, staying between the Tropic of Cancer and Tropic of Capricorn lose their shadows, though momentarily, twice a year. These two moments are called zero shadow moments."
The actual phenomenon only lasts a fraction of a second, but its effect can be seen for up to a minute and a half.