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Friday, February 17, 2023

photographing the most bright and attractive - SUN

SUN !!  Our Sun is a 4.5 billion-year-old star – a hot glowing ball of hydrogen and helium at the center of our solar system. The Sun is about 93 million miles (150 million kilometers) from Earth, and without its energy, life as we know it could not exist here on our home planet.   The Sun is the largest object in our solar system. The Sun’s volume would need 1.3 million Earths to fill it. Its gravity holds the solar system together, keeping everything from the biggest planets to the smallest bits of debris in orbit around it. The hottest part of the Sun is its core, where temperatures top 27 million degrees Fahrenheit (15 million degrees Celsius). 

The NASA NuSTAR mission, or Nuclear Spectroscopic Telescope Array, was able to observe the X-rays released by the hottest spots in the star’s atmosphere. While the telescope can’t view the entirety of the sun from its orbit around the Earth, it took 25 images of high-energy X-rays in the sun’s atmosphere in June.  One of the greatest mysteries about the sun is why its outer atmosphere, or corona, is at least 100 times hotter than its actual surface. Astronomers think the corona’s heat, which reaches a staggering 1 million degrees Celsius (1,800,032 degrees Fahrenheit), could be due to nanoflares — small eruptions in the sun’s atmosphere. 

Miles away ,  the famous resort town of Dehradun,  inside the 250-year-old Survey of India, was in all likelihood the site of one of the most ambitious astronomical undertakings of the late 19th and early 20th centuries. From 1878 to 1925, photographs of the sun were taken here twice every day and dispatched weekly to Britain. At the Survey of India campus are a number of defunct observatories. While the fading sign in front of the derelict Hennessey Observatory states that solar photography commenced there in 1883, no information about the five preceding years is readily available. The only surviving example of this series at the National Survey Museum, from 1905, attributes it to a mysterious Walker Observatory, which is no longer identified. 

The first photograph of the sun was taken in 1845, the first photoheliograph installed at Kew Observatory, London, in 1858, the spectroscope invented in 1860 and, in the shadow of eclipses and the expeditions organised to record them, emerged the modern field of solar physics. In India too, modern astronomical research, under the auspices of the British administration, was not unknown – one will be surprised to know that the Madras Observatory dates back to 1792 ! . 

No Indian photographer is named in the 46 annual reports of the Survey during the period of the programme. Meins’ successors were all natives of Britain: LH Clarke, CF Guthrie, B Rowland and RW Foster. The Indians who are part of this work are grouped under the designation of khalāsi, a term for porters which implies that they were probably personnel who handled and carried the bulky equipment.


Understand that for decades Sun continues to be captured daily from Kodaikanal observatory .. .. and here is a photo of Sun coming out in the morning near Pulicat taken an year or so ago !!

With regards – S. Sampathkumar
Pic taken by me – info collated from various sources !! 

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