In a landmark discovery for physics and astronomy, international scientists including from India, claim to have glimpsed the first direct evidence of gravitational waves, or ripples in space-time. Two US-based underground detectors known as the Laser Interferometer Gravitational-wave Observatory, LIGO, observed the phenomenon. Researchers said Thursday that when two black holes collided some 1.3 billion years ago, the joining of those two great masses sent forth a wobble that hurtled through space and arrived at Earth on September 14, 2015 when it was picked up by the LIGO.<br/><br/>Albert Einstein predicted the existence of these waves in 1916 as a consequence of his General Theory of Relativity.<br/><br/>David Reitze, Eexecutive Director of LIGO project said this is the first time the universe has spoken to us – through gravitational waves.<br/><br/>Scientists say the new data will allow measurements of faraway stars, galaxies and black holes based on the waves they make.<br/><br/>Indian scientists played a crucial role, including in data analysis, in the path-breaking project. Several institutes, including Institute of Plasma Research, Gandhinagar, Inter University Centre for Astronomy and Astrophysics, Pune, and Raja Ramanna Centre for Advanced Technology, Indore, were involved in the research.The announcement of detection of gravitational waves was made simultaneously at IUCAA, Pune, and by scientists in Washington in the United States.<br/><br/>Abhay Ashtekar, the Director of the Institute for Gravitational Physics and Geometry at Pennsylvania State University said it is a matter of pride for us that more than 60 percent of scientists involved in LIGO project were of Indian origin.<br/><br/>Senior scientist at IUCAA, C V Vishveshvara said on this occasion that we have predicted this 10 years back but we were not having equipment's to prove it at that time.<br/><br/>Prime Minister Narendra Modi in a series of tweets said that immensely proud that Indian scientists played an important role in this challenging quest. He said the historic detection of gravitational waves opens up new frontier for understanding of universe. Mr Modi expressed optimism that it will make even bigger contribution with an advanced gravitational wave detector in the country.<br/><br/>Scientists who participated in Laser Interferometer Gravitational-wave Observatory LIGO project have said today in Pune that if LIGO project starts in India, the country will witness scientific revolution.<br/><br/>Prime Minister Narendra Modi Thursday said in his Tweet that the third LIGO detector will be established in India. Scientists gathered again in IUCAA to discuss the findings of LIGO project. One thousand scientists from 16 countries participated in LIGO project including scientists of IUCAA Pune.