Uranus’s Rings: The Discovery and how India lost its share of contribution in it!
William Herschel discovered Uranus in 1781, the 1st planet found with the telescope. He called the planet “The Georgium Sidus” to flatter King George III of England. The name “Uranus”(Greek God) was first proposed by German astronomer Johann Elert Bode in line with the other planetary names – which are from Greek mythology.
Role of Occultation in the discovery of Uranus’s rings: –
Uranus’s rings were discovered in 1977 while observing an occultation. “In astronomy, an occultation occurs when an object (Uranus) passes in front of another object (Star), from the observer’s (i.e. YOUR) perspective.” Occultations are quite rare & important events; As they help the astronomers to unfold some secrets of the universe. So, the astronomers around the world were ready with their elaborate preparations for this event scheduled on 10 March 1977.
Now if you were to search the internet about the discovery of Uranus’s rings, you would probably find that all the credit for this discovery is given to the Americans. To shatter the myth, I would like to describe the happenings of 10 March 1977 here which Professor J. C. Bhattacharya had published in the Bulletins of the Indian Institute of Astrophysics in 1980.
Initially, India was considered to be the best location. But after some re-calculations, it was deduced that the occultation will not be visible from India. The teams of foreign astronomers that had planned to come to India, changed their plans in a hurry. However, the chances of a successful observation from India could not be completely ruled out. Hence the team of Professor J. C. Bhattacharya planned the observation at the Vainu Bappu Observatory in Kavalur, Tamil Nadu. And they were victorious to witness the event with remarkable observations.
Mis-interpretation of Observations: –
So, when Uranus would pass in front of the star, it would temporarily block the star’s light. They were able to observe this event accurately. But in addition to this, they also saw that several minutes before the event, the star had completely disappeared for about 9 seconds and then reappeared again.
This brief hide and seek of the star happened five times before and after the star was actually occulted by planet Uranus, and was recorded by other astronomers too. This observation led Bhattacharya and his colleague Kuppuswamy to suspect that some satellite of Uranus had come in between the Earth and the star. Hence, they published an article in the science magazine Nature (26 May 1977) claiming the discovery of a new satellite of Uranus.
Similar observations were made by two more teams and they came to the same conclusion independently. 1st team led by Dr. Elliot who was observing from NASA’s Kuiper Airborne observatory flying over the Southern Indian Ocean. The 2nd team led by Dr. Robert Millis who was in Perth, West Australia.
Now a few days later, when Dr. Elliot was examining the details of these three reports he concluded that there exists a ring system around Uranus. Hence Dr. Elliot was the first one to claim the existence of Uranus’s rings which he published in Nature (26 May 1977). In it, Elliot has named these rings alpha, beta, gamma, delta, and epsilon in order of their distances from the planet.
This announcement by Elliot made the other observers go over their data once again. Confirmation came from everybody around the world. Even from the other group of observers from India observing from the Uttar Pradesh State Observatory in Nainital.
Still, there were unanswered questions as to declare the existence of a ring system around Uranus. However, finally, after a lot of examination of the records, the scientists of the Indian Institute of Astrophysics also published in Nature (8 December 1977), the existence of Uranus’s rings.
Hence, Elliot was the first one to notice the symmetry in features from pre and post occultation events and confirm the existence of rings around Uranus.
And thus, India lost its contribution to the discovery of the rings of Uranus.
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