The Indian Institute of Astrophysics (IIA), with its headquarters in Bangalore (Karnataka state), is a premier National Research Institute of India. The institute has a network of laboratories and observatories in India, including Kodaikanal (the Kodaikanal Solar Observatory), Kavalur (the Vainu Bappu Observatory), Gauribidanur, Hanle (the Indian Astronomical Observatory) and Hosakote.
The East India Company having resolved to establish an observatory at Madras for promoting the knowledge of Astronomy, Geography and Navigation in India, Sir Charles Oakeley, then President of the Council had the building for the observatory completed by 1792. The Madras series of observations had commenced in 1787(1786)* through the efforts of a member of the Madras Government - William Petrie - who had in his possession two three-inch achromatic telescopes, two astronomical clocks with compound pendulums and an excellent transit instrument. This equipment formed the nucleus of instrumentation of the new observatory, which soon embarked on a series of observations of the stars, the moon, and eclipses of Jupiter's satellites, with the accurate determination of longitude, as its first concern. The pier that carried the original small transit instrument on a massive granite pillar has on it an inscription in Latin, Tamil, Telugu and Hindustani, so that " Posterity may be informed a thousand years hence of the period when the mathematical sciences were first planted by British Liberality in Asia". In any case this quotation from the first annual report of the observatory is atleast a record of the fact that astronomical activity at the Madras Observatory was indeed the first among British efforts at scientific studies in India.
For over a century, the Madras Observatory continued to be the only astronomical observatory in India engaged in systematic measures of star position and brightness. Goldingham, Taylor, Jacob and Pogson were the Government astronomers who dominated activity at Madras. With a new five feet transit, Taylor completed in 1884 his catalogue of places of over 11,000 stars. Double star catalogues, measures of their separation and the determination of their orbits were Jacob's principal interest. The observatory received a new meridian circle during his tenure and with it, besides observations for the determination of star position and evaluation of proper motions, a series of observations of the satellites of Jupiter and Saturn were commenced. From 1861 until his death in 1891, N. R. Pogson as Government astronomer, in keeping with progress in the science, entered into newer areas of observations. While the transit instrument and the meridian circle were both usefully utilized for a star catalogue of 3000 stars that included standard stars, large proper motion stars, variable stars and the like, it is with the new 8 - inch Cooke equatorial that he made discoveries of asteroids and variable stars. The asteroids Asia, Sappho, Sylvia, Camilla, Vera and the Variable stars Y Virginis, U Scorpii, T Sagittari, Z Virginis, X Capricorni and R.Reticuli were all first discovered visually at Madras either with the transit instrument or by the equatorial instruments. The discovery in 1867 of the light variation of R.Reticuli by C. Raghunathachary is perhaps the first astronomical discovery by an Indian in recent history. Pogson also undertook the preparation of a catalogue and atlas of variable stars, complete with magnitude estimates made by him both of the comparison and the variable. These were edited by Turner after Pogson's death.
During this period the Madras observatory participated in observations of the important total solar eclipses that were visible from India during the nineteenth century. These were the eclipses that established the foundations of astrophysics and especially of solar physics, and in these observations the Madras observatory's contributions were most significant. The first one of August 18, 1868 created the subject of solar physics, for at this eclipse the spectroscope was used for the first time to discover the gaseous nature of the prominences. The hydrogen emission lines seen in the prominence were so strong that the French astronomer Jansen reasoned they could be seen without the eclipse. The next day at the eclipse site the speculation was proved to be correct, making it possible for daily surveys of prominences thereafter, without the need of a total eclipse.
There were several eclipse teams scattered over the path of totality for this vital eclipse. The Madras Observatory had two teams, one at Wanarpati and the other Masulipatam. Clouds at Wanarpati interfered with the success of the expedition. At Masulipatam, Pogson detected the hydrogen lines in emission, as had all the teams that had a programme of observation with the spectroscope. They also saw a bright yellow line near the position of the D lines of sodium. The line originated from a hitherto unknown element later termed helium, after the source of its earliest detection.
On June 6, 1872 an annular eclipse was visible at madras. Pogson examining the region close to the moon's limb found the bright chromospheric Spectrum flash out for a short duration on the formation and again at the breaking up of the annulus. This is the first observation on record of viewing the flash spectrum at an annular eclipse.