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#WeatherSays | This image is a depiction of the Sun's path over a period from February - September 2020, and will continue for one year. One photo from each cloud-free day has been blended to make a figure of 8 which is called an #analemma.
(@ajaytalwar)
➡️The north-south component of the analemma results from the change on Sun's declination due to the tilt of Earth's axis of rotation.
➡️The east-west component results from the non-uniform rate of change of the Sun's right ascension, governed by combined effects of Earth's axial tilt and orbital eccentricity.
➡️This particular analemma is rather special. It contains an annular eclipse right on top of the figure. The solstice eclipse which happened on 21 June in India. This is called a "Tutelemma".
➡️To make this image, the camera was kept facing the same direction (south) and at the same altitude above the horizon (45°) for each shot at my home terrace in Gurugram.
➡️The background image is of Chilla Sahib Gurudwara at Sirsa, using exact same direction (south) and altitude above horizon 43.8° as Sirsa is 1.2° North of Gurugram.
➡️The effect of the difference between the longitudes of Gurugram and Sirsa is compensated by clicking the Gurugram images earlier than the predicted eclipse time so that the Sun's position in the sky remains the same.
➡️The image of the Annular eclipse was clicked at Sirsa at the time of the middle of annularity, with the exact same camera orientation as the #GurudwaraChillaSahib.
The imaging process to complete the Tutelemma will continue till February 2021.
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