Artist’s concept illustration of a supermassive black hole emitting an x-ray jet.

An international team of researchers, led by postgraduate student Alexis Andrés, has found that the black hole at the center of our galaxy, Sagittarius A*, not only flares irregularly from day to day but also in the long term.

Astronomers have known for decades that Sagittarius A* flashes every day, emitting bursts of radiation that are ten to a hundred times brighter than normal signals observed from the black hole.

To find out more about these mysterious flares, the team of astronomers, led by Andrés, searched for patterns in 15 years of data made available by NASA’s Neil Gehrels Swift Observatory, an Earth-orbiting satellite dedicated to the detection of gamma-ray bursts.

The Swift Observatory has been observing gamma rays from black hole since 2006.

In the next few years, the team of astronomers expect to gather enough data to be able to rule out whether the variations in the flares from Sagittarius A* are due to passing gaseous clouds or stars, or whether something else can explain the irregular activity observed from our galaxy’s central black hole.

“The long dataset of the Swift observatory did not just happen by accident,” says co-author and previous supervisor to Andrés, Dr.

It was previously thought that more flares follow after gaseous clouds or stars pass by the black hole, but there is no evidence for that yet.

Reference: “A Swift study of long-term changes in the X-ray flaring properties of Sagittarius A” by A Andrés, J van den Eijnden, N Degenaar, P A Evans, K Chatterjee, M Reynolds, J M Miller, J Kennea, R Wijnands, S Markoff, D Altamirano, C O Heinke, A Bahramian and G Ponti, D Haggard, 9 December 2021, Monthly Notices of the Royal Astronomical Society.

January 13, 2022

January 13, 2022

January 13, 2022

January 13, 2022

January 13, 2022