Bhubaneswar: The Capital witnessed Zero Shadow Day (ZSD) – an interesting celestial phenomenon Monday. At 11:43am, a large number of science enthusiasts gathered at Pathani Samanta Planetarium in the city to experience zero shadow moment. Planetarium officials placed four poles over white papers under the Sun and waited for the shadow to disappear. They also showed the interesting phenomenon to the visitors. “Shadows disappear for a few minutes on Zero Shadow Day.
The Sun was exactly over head at 90° angle to the earth’s surface and the Sunlight was vertical for which shadows merged with the object for four minutes. This rare event occurs twice a year between the tropics of Cancer and
Capricorn,” planetarium deputy director Subhendu Pattnaik told Orissa POST. Explaining the ZSD occurrence, Pattnaik said, “Uttarayan (movement of the Sun from the Equator to the tropic of Cancer) and Dakshinayan (back from autumnal equinox to Capricorn in the south) take place because of earth’s rotation on its axis which is tilted at an angle of 23.5° to the axis of revolution around the Sun.”
Adding further about the event he said, “ZSD occurs in different locations at different times. It takes place twice in Odisha – May-June and in July. Bhubaneswar witnessed ZSD occurrence Monday, people of Cuttack will get a glimpse of it May 22 while denizens in Burla can experience ZSD May 28. People of Rourkela can see it June 2.”
Unfortunately, ZSD is unknown to many in Bhubaneswar. On this occasion, the planetarium demonstrated zero shadow moment to the visitors. “We have planned to hold a workshop in Burla May 28 for science enthusiasts. Such activities will help measure the earth’s diameter and Sun’s inclination, Pattnaik said.
Ayesha Patra, a student of a private school, was surprised when she witnessed the event. “I never knew, there is this phenomenon of zero shadow moment. Today’s activity created interest in me to know more about the phenomenon.” A science enthusiast, Patyush Maharana of Nayapalli, said, “We know solar and lunar eclipses happen, but we don’t have any idea about zero shadow occurrence. When I heard that a live display will be held at this planetarium, I wasted no time and came here straight. It was interesting to watch the shadow gradually hide under the subject.” Over 200 visitors watched the zero shadow moment at the planetarium.
AQUARIUS