Indian scientists have discovered an extremely large supercluster of galaxies, which is as big as 20 million billion suns. Pune-based Inter University Centre for Astronomy and Astrophysics, IUCAA team of astronomers has named it Saraswati.<br/><br/>IUCAA said today, this is one of the largest known structures in the neighbourhood of the universe, 4,000 million light-years away from Earth and roughly more than 10 billion years old. Its mass extends over the scale of 600 million light years.<br/><br/>Scientists of this institute were also involved in last year's path-breaking discovery of gravitational waves.<br/><br/>The findings have been published in the latest issue of The Astrophysical Journal, the premier research journal of the American Astronomical Society.<br/><br/>Superclusters are the largest coherent structures in the cosmic web. They are a chain of galaxies and galaxy clusters, bound by gravity, often stretching to several hundred times the size of clusters of galaxies.