<P> The Himalayan Chandra Telescope is a 2.01 meters (6.5 feet) diameter optical - infrared telescope named after India - born Nobel laureate Subrahmanyam Chandrasekhar . It contains a modified Ritchey - Chretien system with a primary mirror made of ULE ceramic which is designed to withstand low temperatures it experiences . The telescope was manufactured by Electo - Optical System Technologies Inc. at Tucson, Arizona, USA . The telescope is mounted with 3 science instruments called Himalaya Faint Object Spectrograph (HFOSC), the near - IR imager and the optical CCD imager . The telescope is remotely operated via an INSAT - 3B satellite link which allows operation even in sub-zero temperatures in winter . </P> <P> The High Altitude Gamma Ray Telescope (HAGAR) is an atmospheric Cerenkov experiment with 7 telescopes setup in 2008 . Each telescope has 7 mirrors with a total area of 4.4 square meters . The telescopes are deployed on the periphery of a circle of radius 50 meters with one telescope at the center . Each telescope has alt - azimuth mounting . </P> <P> The Center for Research and Education in Science and Technology (CREST) is situated 35 km to the northeast of Bangalore near Hoskote town . The Center houses the control room for the remote operations of the 2m Himalayan Chandra Telescope (HCT) at the Indian Astronomical Observatory, Hanle, and the HCT data archive . The operations are controlled using a remote satellite link . </P> <P> The Indian Institute of Astrophysics is collaborating with the McDonnell Center for the Space Sciences of Washington University in St. Louis, US to operate two 0.5 meters Cassegrain telescopes to monitor active galactic nuclei . One of the observatories is to be established in Hanle . The facilities 180 degrees apart in longitude are together to be called the Antipodal Transient Observatory (ATO). </P>

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