What happens when two black holes collide? Scientists at Laser Interferometer Gravitational-Wave Observatory (LIGO) say that they fuse to form one black hole and the incident doesn't go down quietly. Apparently, when something like this happens, huge gravitational waves are produced that ripple across the fabric of space and time, and LIGO knows this because it heard it happen.
LIGO first detected the waves back in February and have confirmed the recording when more waves made it to the earth on Wednesday.
"This second [discovery] should convince anyone who was sceptical of the first discovery that this isn't a fluke," Dave Reitze, executive director of the LIGO Lab, run out of MIT and Caltech, told Vox. "We've now seen two of these binary black hole collisions emerging to form a new black hole — this is something no other type of observatory has been able to see before. ... Gravitational wave astronomy is for real."
While our observations of the universe so far have been only through the detection of electromagnetic radiation such as x-rays, gamma rays and visible light, with gravitational waves, we could study a lot of things happening in the universe that don't emit electromagnetic waves, like, say, the after effects of the Big Bang, the Vox report added.
According to LIGO, the detection of gravitational waves also confirms Albert Einstein's prediction from his general theory of relativity.
LIGO will be making a second observation later this year with improved sensitivity and expect to see more collisions like binary neutron-star mergers. The organization also believes that the Vigo, another gravitational wave detecting system will greatly help narrow down the source of the next set of observed waves.
Interestingly, these waves were detected thanks to an India scientist — Professor Sanjeev Dhurandhar of the Inter-University Centre of Astronomy and Astrophysics (IUCAA) in Pune. In 1991, he had authored a paper on the subject.
"He showed how to extract gravitational wave signals from noisy data. The method through which the gravitational waves have been discovered by LIGO was built on the basis of his proposal," Prof Tarun Souradeep of IUCAA and spokesperson of the Indian Initiative in Gravitational-Wave Observations (IndIGO) told International Business Times, India, earlier.
In addition, India will also be receiving a LIGO observatory. Apparently, the Institute for Plasma Research (IPR), Gandhinagar, Gujarat, is going to build the world's most advanced LIGO to detect gravitational waves.