Vainu Bappu Observatory

The Vainu Bappu Observatory, or VBO for short, is an astronomical observatory owned and operated by Indian Institute of Astrophysics. It is located in the Javadi Hills near the town of Kavalur in the Indian state of Tamil Nadu, 175 km south-east of Bangalore.

Equipment

The observatory is home to the Vainu Bappu Telescope, which the Indian Institute of Astrophysics claims as the largest telescope in Asia. It has a diameter of 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-Perot interferometer.

* Technical Details
** Primary Mirror Diameter: 234 cm
** Prime focus: f/3.25 with a scale of 27".1/mm
** Cassegrain focus: f/13 with a scale of 6".8/mm
** Guiding: remote, manual guiding

* Instruments Available
** At PRIME focus:
*** Imaging Camera with a 3-element Wynne corrector
** At CASSEGRAIN focus:
*** Medium resolution Spectroploarimeter
*** Medium resolution Optometrics Research Spectrograph (OMRS)

* Detector
** 1024x1024 pixels TEK CCD, with a pixel size of 24 micrometres

Discoveries

The 1 metre telescope is associated with two unique discoveries in the solar system. In the year 1972, atmosphere was detected around Jupiter's satellite Ganymede and in 1977 rings were discovered around the planet Uranus. In 1984 Kavalur reported the discovery of a thin outer ring around Saturn.

On 17th February, 1988 a new minor planet was discovered using the 45 cm Schmidt telescope. It has been named 4130 Ramanujan after the Indian mathematical genius Srinivasa Ramanujan. This is the first such discovery from India in this century.

cientific activities

Front-line research is being carried out with the help of the optical telescopes at Vainu Bappu Observatory using several focal plane instrumentational facilities. The ongoing programmes include observations of stars, star clusters, novae, supernovae, blazars, galaxies, optical imaging of gamma-ray burst fields, stellar populations, solar system objects and many others.

The telescopes at the observatory had started with relatively modest focal plane instruments and later on graduated to more sophisticated ones. These include cameras for fast photography, photoelectric photometers, a single-channel photoelectric spectrum scanner, a medium resolution spectrograph, a quartz-prism calibration spectrograph, infrared photometer, image tube spectrograph, a Universal Astronomical Grating Spectrograph (UAGS from Zeiss), high-resolution echelle spectrograph and a polarimeter. Photographic plates were the principal detectors in the early days. Presently the charge-coupled devices (CCD) have replaced the photographic plates. Some micro-processor-controlled photon counting systems were designed and fabricated which have been used in a variety of observational projects. A fibre linked echelle spectrograph is under construction.

On campus maintenance facilities like aluminising plants for coating the telescope mirrors, mechanical and electrical workshops, electronics labs, along with a liquid nitrogen plant are at hand for the smooth functioning of the observatory. Highly advanced technical facilities like SUN workstations are available at the telescopes for handling the CCD data, along with specialised data reduction packages such as IRAF, STSDAS and DAOPHOT. Communication facilities, like e-mail via VSAT satellite connection, are available for all users for the telescopes.

A programme of ultralow dispersion spectroscopy was successfully used to survey stars in the Large Magellanic Cloud (LMC). Of the ten supernovae observed so far, SN1987A in LMC was observed in great detail using the 1 m and the 75 cm telescopes despite its low elevation in the southern sky, proving the worth of the geographic location of Kavalur. In fact the observations of the supernova were started within 48 hours of the discovery.

Observational studies of evolved stars, in particular studies related to their evolutionary aspects, carried out at this observatory, have received critical acclaim and international recognition. The observational facilities at this Observatory have yielded many Ph.D theses for the scholars of the Institute as well as of other institutes and universities in the country

Field stations

While the Vainu Bappu Observatory is one of the field stations of the Bangalore-based Indian Institute of Astrophysics, which is primarily devoted to research activities using the optical telescopes, the other field stations at the Kodaikanal Solar Observatory and at Gauribidanur are equipped for solar observations and radio astronomy programmes respectively.

A present one of the challenging projects undertaken by the Institute is the installation of a 2 metre remotely operated optical and infrared telescope at Hanle in the Ladakh region of Himalayas. This will be the highest ground-based telescope in the world. A new field station called Centre for Research and Education in Science and Technology (CREST) is also being set up at Hosakote near Bangalore.

External links

* [http://www.iisc.ernet.in/~astro/vbo.html www.iisc.ernet.in/~astro/vbo.html]