AstroSat Launched by ISRO Discovers One of the Earliest Galaxies Thus Marking a Major Breakthrough

AstroSat, India’s first multi-wavelength satellite which was launched on 28 September 2020 on a PSLV-XL by ISRO with five major science instruments onboard, has detected extreme-UV light from a galaxy, called AUDFs01, 9.3 billion light-years away from Earth. AstroSat has five unique X-ray and ultraviolet telescopes working in tandem.

Terming the development as a major breakthrough, the Indian Space Research Organisation (ISRO) says that the discovery was made by an international team of astronomers led by Dr Kanak Saha, at the Inter-University Centre for Astronomy and Astrophysics (IUCAA), Pune and reported in Nature Astronomy. This team includes scientists from India, Switzerland, France, The USA, Japan and The Netherlands.

Dr Saha and his team observed the galaxy which is located in the Hubble Extreme Deep field, through AstroSat. Since UV radiation is absorbed by Earth’s atmosphere, it can only be observed from Space. “AstroSat/UVIT was able to achieve this unique feat because the background noise in the UVIT detector is much less than the ones on Hubble Space Telescope”, said Dr. Saha. “The excellent spatial resolution, and high sensitivity, a tribute to the hard work of UVIT core team over a decade, were key to the detection of this very weak source”, said Prof Tandon.

The Ultra Violet Imaging Telescope (UVIT), which is capable of simultaneous imaging in far and near-ultraviolet bands with a wide field of view, was developed by teams from IIA, IUCAA, and TIFR from India, and CSA of Canada under the leadership of Shyam Tandon, ExEmeritus Professor, IUCAA with the full support of ISRO, says the official website.