ESA Science & Technology - Black hole at the core of distant galaxy periodically brightens up

An X-ray view of the active black hole at the core of distant galaxy GSN 069, about 250 million light years away, based on data from ESA's XMM-Newton X-ray observatory. The upper part of the animation shows the actual observations, and the graph in the lower part shows variations of the X-ray brightness of the source relative to its ‘dormant’ level.

This animation is based on nearly 40 hours of observations of this source, which undergoes never-before-seen flashes – dubbed 'quasi-periodic eruptions', or QPEs – every nine hours. The sequence has been speeded up for illustration purposes; each frame corresponds to about three minutes of actual XMM-Newton exposure time.

These flares were first detected on 24 December 2018, when the source was observed to suddenly increase its brightness by up to a factor 100, then dimmed back to its normal levels within one hour and lit up again nine hours later.

Although never before observed, scientists think periodic flares like these might actually be quite common in the Universe.