Vainu Bappu Observatory 2.3 meters and was first used in 1986. Along with the Vainu Bappu telescope, the observatory has two other telescopes: A 1-meter Zeiss manufactured and another 75-centimeter Cassegrain reflector currently being refurbished. The observatory also has a Fabry–Pérot interferometer. The 1-metre telescope is associated with two unique discoveries in the solar system. In 1972, atmosphere was detected around Jupiter's satellite Ganymede and in the year 1977, participated in the observations that confirmed rings were discovered around the planet Uranus. In 1984, Kavalur reported the discovery of a thin outer ring around Saturn. On 17 February 1988, a new minor planet
Eris (dwarf planet) Eris appeared to be larger than Pluto, NASA initially described it as the Solar System's tenth planet. This, along with the prospect of other objects of similar size being discovered in the future, motivated the International Astronomical Union (IAU) to define the term "planet" for the first time. Under the IAU definition approved on August 24, 2006, Eris is a "dwarf planet", along with objects such as Pluto, Ceres, Haumea and Makemake, thereby reducing the number of known planets in the Solar System to eight, the same as before Pluto's discovery in 1930. Observations of a stellar occultation by Eris