Interpreting Ancient Indian Hindu Geo-centric Astronomy in terms of Modern Astronomy requires a host of skills. These scholars studied the manuscripts and critically analysed them, making corrections to the bits that were worn out. They were experts in Sanskrit, English, Astronomy (Ancient and Modern), and Mathematics.
They have given us the first good translations of Ancient Astronomical texts. Where western scholars did not understand and wrote disparaging comments, these scholars put decades of work and gave us good interpretations and translations because of their background in Vaidika Tradition and Indian Culture.
The only information I could find online about Prof. T.S. Kuppana Sastry is in the preface to his work on Lagadha’s Vedanga Jyotisha, written by Prof. K.V. Sarma.
More Information about Prof. K.V. Sarma can be found here : http://kvsarmaresearchfoundation.in
Prof. Sarma’s main field of research was Indian Astronomy and Mathematics and Manuscriptology. Apart from these he has worked on Vedas, Religion, Philosophy, Epics and Puranas and also on general Literature in Sanskrit.
There is library , with priceless manuscripts, in Adyar Chennai, to honour his memory : http://www.thehindu.com/features/metroplus/society/repository-of-a-priceless-heritage/article6189972.ece
Source : https://archive.org/stream/PanchaSiddhantika/Pancha-siddhantika_djvu.txt Professor T.S. Sastry (1900-1982), M.A., L.T., was a polymath. A Sanskritist by profession, he was also a keen student of the sciences, both eastern and western. His forte was early Indian astronomy, which he studied in comparison with modern astronomy. The combination had given him the insight and analytical skill to understand and appreciate early ' Indian astronomy in terms of modern astronomy. His pubiications include critical editions of the Mahdbhdskariya of Bhaskara I with two commentaries, and the Vedanga Jyotisa with Translation and detailed notes. Jointly with K. V. Sarma, he edited the Vdkyakarand of Vararuci with commentary. A number of papers which he wrote on Indian astronomy have been collected together.and issued under the title Collected Papers on Jyotisha (Kendriya Sanskrit Vidyapeetha, Tirupati, 1989). Professor K.V. Sarma, (b.1919), B.Sc., M.A. (Skt), D.Litt. (History of Astronomy), formerly Director of the wellknown V.V. Institute of Sanskrit and Indological Studies, Hoshiarpur (Punjab), and presently Hon. Professor of Sanskrit, Adyar Library and Research Centre, Madras, has been a student of Indian astronomy for nearly Forty years. He has edited and translated a large number of astronomical texts, mainly produced in Kerala. These include Drgganita, Grahacdranibandhana, Tantrasahgr'aha, Sphutanirnaya, Rdsigolasphutdn iti , Goladipikd, Candrasphutdpti and Jyotirmimaihsd. He is the author, jointly, of Indian Astronomy : A Source Book (Bombay, 1985). His writings include also about 250 research papers on different subjects including Indian astronomy. Respectful namsaskārā: to these and other pioneers.