A Tour of the Biggest Explosion Ever Seen in the Universe

The biggest explosion seen in the universe has been found. This record-breaking, gargantuan eruption came from a black hole in a distant galaxy cluster hundreds of millions of light years away.

Astronomers made this record-breaking discovery using X-ray data from NASA's Chandra X-ray Observatory and ESA's XMM-Newton, and radio data from the Murchison Widefield Array in Australia and the Giant Metrewave Radio Telescope in India.

The unrivaled outburst was detected in the Ophiuchus galaxy cluster, which is about 390 million light years from Earth. Galaxy clusters are the largest structures in the Universe held together by gravity, containing thousands of individual galaxies, dark matter, and hot gas.

In the center of the Ophiuchus cluster, there is a large galaxy that contains a supermassive black hole. Researchers have traced the likely source of this gigantic eruption to this black hole.

Although black holes are famous for pulling material toward them, they often expel prodigious amounts of material and energy. This happens when matter falling toward the black hole is redirected into jets, or beams, that blast outward into space and slam into any surrounding material.

Astronomers needed to combine the X-ray information along with the radio data in order to clinch this finding. They discovered that a cavity in the hot gas, first seen in Chandra data in 2016, was filled almost perfectly with radio emission created by electrons that had been accelerated to nearly the speed of light. This allowed them to confirm that an explosion of unprecedented size took place in Ophiuchus.

The amount of energy required to create the cavity in Ophiuchus is about five times greater than the previous record holder, MS 0735+74, and hundreds and thousands of times greater than typical clusters.

The black hole eruption must have finished because the researchers do not see any evidence for current jets in the radio data. This shutdown can be explained by the Chandra data, which show that the densest and coolest gas seen in X-rays is currently located at a different position from the central galaxy. If this gas shifted away from the galaxy it will have deprived the black hole of fuel for its growth, turning off the jets.

While much has been learned about the galaxy cluster Ophiuchus through X-ray and radio telescopes, more data will be needed to answer the many remaining questions this object poses.