Indian Astronomical Observatory

Indian Astronomical Observatory

Indian Astronomical Observatory, Hanle
Organization	Indian Institute of Astrophysics
Location	Hanle, India
Coordinates	32°46′46″N 78°57′51″E / 32.77944°N 78.96417°E / 32.77944; 78.96417
Altitude	4,500 m (14,764 ft)
Established	2001
Website	Indian Astronomical Observatory
Telescopes
Himalayan Chandra Telescope 2.01 m Ritchey-Chretien, remotely operated optical-infrared telescope HAGAR Gamma Ray Telescope
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The Indian Astronomical Observatory (IAO), located near Leh in Ladakh, India, has one of the world's highest sites for optical, infrared and gamma-ray telescopes. It is operated by the Indian Institute of Astrophysics, Bangalore. It is currently the second highest optical telescope in the world, situated at an elevation of 4,500 meters (14,764 ft).

The Indian Astronomical Observatory stands on Mt. Saraswati, Digpa-ratsa Ri, Hanle in south-eastern Ladakh in the eastern Jammu and Kashmir state of India. Accessing the observatory, located near the Chinese border, requires a ten-hour drive from Leh, the district capital of Ladakh.

In the late 1980s a committee chaired by Prof. B. V. Sreekantan recommended that a national large optical telescope be taken up as a priority project. The search for the site of the observatory was taken up in 1992 under the leadership of Prof. Arvind Bhatnagar. The scientists from the Indian Institute of Astrophysics found the site at Hanle.

The first light was seen by the Observatory 2-metre telescope on the midnight hour between 26 September and 27 September 2000.

The satellite link between the Centre for Research and Education in Science and Technology (CREST), Bangalore and Hanle was inaugurated by the then Jammu and Kashmir Chief Minister Dr. Farooq Abdullah on 2 June 2001. The Observatory was dedicated to the nation on 29 August 2001.

The Hanle site is deemed to be excellent for visible, infrared and submillimeter observations throughout the year. Specifically the observation conditions yield about 255 spectroscopic nights per year, approximately 190 photometric nights per year and an annual rain plus snow precipitation of less than 10 cm. In addition, there are low ambient temperatures, low humidity, low concentration of atmospheric aerosols, low atmospheric water vapour, dark nights and low pollution.