2 years after Cabinet nod, India begins to set up gravitational wave observatory

New Delhi: Nearly two years after the Union Cabinet’s approval, the first step has been taken this week to construct one of the world’s most sophisticated scientific experimental facilities in central India to detect the ultra feeble gravitational waves that open up a new window to look at the universe.

To be constructed over the next 48 months at a cost of Rs 1,600 crore, the Laser Interferometer Gravitational-wave Observatory (LIGO) will come up at Aundha in Hingoli district in Maharashtra, as per the tender document released by the Department of Atomic Energy.

“We selected the site because of low background seismic noise as detectors are very sensitive. Also the area has very less rain and wind. Both can disturb the observations,” Sanjit Mitra, a senior scientist at Inter University Centre for Astronomy and Astrophysics, Pune, who is closely associated with the project, told DH.

The Indian facility will be a part of a chain of three such observatories, other two being at Hanford and Livingston in the USA.

The L-shaped observatory will have two 4-km long vacuum tunnels to house highly sensitive sensors to pick up the feeble signals emanating from violent cosmic events like merger of black holes and neutron stars taking place in distant universe.

Indian astrophysicists were waiting for the observatory for a long time after it was approved “in-principle” by the Union government in 2016 but the cabinet nod for the Rs 2,600 crore project came only in April 2023 and a month later Prime Minister Narendra Modi laid the project foundation stone.

While Rs 1,600 crore is the estimated budget to construct the observatory, the remaining Rs 1,000 crore would be spent on procuring the sensors and detectors.

LIGO-India was one of the mega-science projects proposed by the Planning Commission in 2011. A year later, the National Science Board in the USA gave its nod for shifting one of the US gravitational wave detectors to an Indian site.

The Indian observatory will possibly be the last of the such 4-km sized gravitational wave observatories worldwide. Besides the USA, there are similar facilities in Europe and Japan.