India's Ladakh to Receive Two New Telescopes and Significant Upgrade for Astronomy
In a landmark move for observational astronomy, India is set to establish two new telescopes and upgrade an existing one in Ladakh. This initiative, sanctioned in the recent Union Budget, aims to enhance India's capabilities in studying the sun and the origins of the universe, positioning the country as a leader in astronomical research.
Ladakh: A Hub for Astronomical Excellence
Ladakh is already a premier center for astronomy in India, hosting numerous telescopes. The village of Hanle has been designated as India's first and only Dark Sky Reserve, protecting the natural darkness of the night sky. This new development is expected to significantly boost observational astronomy in India and the Global South, offering unprecedented opportunities for scientific discovery.
National Large Solar Telescope (NLST)
The National Large Solar Telescope (NLST) is a 2-metre aperture solar telescope to be located in the Merak region near Pangong Tso lake. It will operate in the visible and near-infrared wavelengths of the electromagnetic spectrum. Solar physicists will use NLST to study fundamental solar dynamics, magnetism, energetic solar events, and space-weather processes that impact Earth and national space assets like satellites and space launches.
Once operational in approximately 5-6 years, NLST will become India's third ground-based solar observatory, joining the Kodaikanal Solar Observatory (established 1899) and the Udaipur Solar Observatory (established 1975). Combined with data from ISRO's Aditya-L1 space-based solar observatory launched in 2023, NLST will reinforce India's leadership in heliophysics.
National Large Optical-Near Infrared Telescope (NLOT)
The second new facility is the National Large Optical–Near Infrared Telescope (NLOT), a 13.7-metre aperture segmented-mirror telescope to be built in Hanle. Its primary mirror will consist of 90 smaller hexagonal segments arranged to function as a single large mirror. Expected to be ready within the next decade, NLOT will be one of the world's largest telescopes operating in optical-infrared wavelengths.
Ladakh's high altitude, cold and dry atmospheric conditions, and clear skies will minimize diffraction, ensuring high-quality data. NLOT will enable frontier research on exoplanets, stellar and galactic evolution, supernovae, and clues to the origins of the universe. India's experience from participating in the Thirty Meter Telescope (TMT) international project, where it contributes to mirror design and segments, will facilitate NLOT's construction.
Upgraded Himalayan Chandra Telescope (HCT)
In addition to the new telescopes, the government has approved the upgradation of the 2-metre Himalayan Chandra Telescope (HCT), which has been operational for 25 years in Ladakh. The upgraded HCT will feature a 3.7-metre segmented primary mirror and operate in optical-infrared wavelengths. It will complement international facilities like LIGO-India in Maharashtra and the Square Kilometre Array in Australia and South Africa, enhancing studies in transient astronomy and gravitational waves.
Significance of the New Telescopes
Both NLST and NLOT are unique in their respective wavelengths for this longitude and region, offering Indian scientists a major advantage over existing global telescopes by generating previously unavailable data. They will also provide preferential observation time for Indian proposals, making them game-changers for astronomy in India and worldwide. This development marks a significant step forward in advancing our understanding of the cosmos and solidifying India's role in global astronomical research.
