The Indian Astronomical Observatory (IAO), established in 2001, is one of the highest astronomical observatories in the world. It is located at Hanle, Ladakh, on Mt. Saraswati (Digaparatsari) at an altitude of 4,500 meters (14,764 feet) above sea level. The observatory is operated by the Indian Institute of Astrophysics (IIA), Bengaluru.
Key Features of the Indian Astronomical Observatory (IAO), Hanle
- Second-Highest Optical Telescope in the World
IAO is home to the Himalayan Chandra Telescope (HCT), which is one of the highest optical telescopes in the world.
The highest optical telescope is the University of Tokyo Atacama Observatory (TAO) in Chile at 5,640 m (18,500 ft).
- Himalayan Chandra Telescope (HCT)
Installed in 2001, HCT is a 2.01-meter (79-inch) infrared-optical telescope.
Named after Subrahmanyan Chandrasekhar, the Indian-American astrophysicist who won the Nobel Prize in Physics (1983).
Used for studying supernovae, galaxies, variable stars, quasars, and gamma-ray bursts.
- GROWTH-India Telescope
India’s first robotic telescope, operational since June 12, 2018.
Part of the Global Relay of Observatories Watching Transients Happen (GROWTH) initiative for transient astronomy (supernovae, gamma-ray bursts, gravitational wave counterparts).
- High-Altitude Advantage – Best for Astronomy
Dry climate and clear skies make Hanle an ideal location for astronomical observations.
Low atmospheric disturbance and minimal light pollution enable high-precision studies.
Conditions similar to Chile’s Atacama Desert, home to the world’s most advanced telescopes.
- Future Projects: India’s Role in Global Astronomy
Thirty Meter Telescope (TMT) – India is a major contributor to this international project in Hawaii, USA.
LIGO-India – India’s upcoming gravitational wave observatory will complement the LIGO (USA) network.
National Large Optical Telescope (NLOT) – Proposed 10-meter class telescope to further boost Indian astronomy.
Strengthens India’s position in global space research and observational astronomy.
Helps Indian astronomers collaborate on international space missions and discoveries.
Contributes to multi-wavelength and multi-messenger astronomy, studying objects from radio waves to X-rays.
IAO, Hanle, remains one of India’s most important astronomical research centers, playing a key role in cutting-edge discoveries and global collaborations.
