Gamma-ray bursts (GRBs)

Astronomers discovered the largest feature in the universe, which lies 5 billion light years across.

A Hungarian-US team of astronomers have found what appears to be the largest feature in the observable universe: a ring of nine gamma ray bursts – and hence galaxies – 5 billion light years across.

Above: An image of the distribution of GRBs (Gamma-ray bursts) on the sky at a distance of 7 billion light years, centred on the newly discovered ring. The positions of the GRBs are marked by blue dots and the Milky Way is indicated for reference, running from left to right across the image. Credit: L. Balazs.

Gamma-ray bursts (GRBs) are the most luminous events in the universe, releasing as much energy in a few seconds as the Sun does over its 10 billion year lifetime. They are thought to be the result of massive stars collapsing into black holes. Their huge luminosity helps astronomers to map out the location of distant galaxies, something the team exploited.

“If the ring represents a real spatial structure, then it has to be seen nearly face-on because of the small variations of GRB distances around the object’s center. The ring could though instead be a projection of a sphere, where the GRBs all occurred within a 250 million year period, a short timescale compared with the age of the universe.”

source Royal Astronomical Society