• Cabinet has recently approved Laser Gravitational-Wave Observatories (LIGO)-India, a gravitational-wave detector to be built in Hingoli, Maharashtra.
• It is estimated to be built by 2030.
• LIGO will be built by Department of Atomic Energy and the Department of Science and Technology with an MoU with the U.S. National Science Foundation.
• The observatory will be the third of its kind. It is made to the exact specifications of the twin LIGO, in Louisiana and Washington in the U.S.
• A fourth detector in Kagra, Japan, is in the pipeline.
• Four comparable detectors need to be operating simultaneously around the globe to localise a source of gravitational waves anywhere in the sky.

About LIGO

• LIGO currently consists of two interferometers, each with two 4 km long arms arranged in the shape of an “L”.
• These instruments act as ‘antennae’ to detect gravitational waves.
• It comprises stable high-power lasers, precisely figured mirrors, etc.

About Gravitational Waves (GW):

• When two massive objects collide, they create a ripple in space and time in such a way that waves of undulating space-time would propagate in all directions away from the source.
• Predicted in Einstein’s General Theory of Relativity (1915)
• They travel at the speed of light, carrying with them information about their origins