BENGALURU, INDIA, April 18, 2024 (Indian Express): A three-minute-long Surya Tilak ceremony — where a beam of sunlight was projected onto the forehead of Lord Ram’s murti — was performed at noon on Wednesday (April 17) in Ayodhya’s newly-built Ram temple, marking the occasion of Ram Navami. This was achieved using a special mirror-lens arrangement, designed by astronomers at the Indian Institute of Astrophysics (IIA), Bengaluru, that has been installed in the building by a team from the Central Building Research Institute, Roorkee.

When following the Gregorian calendar, the date of Ram Navami (the Hindu festival celebrating the birth of Lord Ram) varies each year. This is because the Gregorian calendar is a solar calendar (based on Earth’s revolution around the Sun — one revolution equals to one year), while the Hindu calendar is a lunar calendar (based on the Moon’s revolution around Earth — one revolution equals to one month). A solar year has roughly 365 days, whereas a lunar year is roughly 354 days long. Given that the IIA team’s brief was to channelize the sun’s rays such that they fall on the Ram murti’s forehead on Ram Navami, its first task was to calculate the position of the Sun in the sky on that day in any given year. After astronomers estimated where the Sun will be in the sky, their second task was to channelize the sunbeam “in a manner that it will fall on the murti’s forehead for a certain amount of time,” Annapurni Subramaniam, Director IIA, said.

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