‘Heart’ Of Black Hole Still Beating After 10 Years

The first confirmed heartbeat of a supermassive black hole is still going strong more than ten years after first being observed. X-ray satellite observations spotted the repeated beat after its signal had been blocked by our Sun for a number of years. Astronomers say this is the most long lived heartbeat ever seen in a black hole and tells us more about the size and structure close to its event horizon – the space around a black hole from which nothing, including light, can escape.

The black hole’s heartbeat was first detected in 2007 at the centre of a galaxy called RE J1034+396 which is approximately 600 million light years from Earth. The signal from this galactic giant repeated every hour and this behaviour was seen in several snapshots taken before satellite observations were blocked by our Sun in 2011. In 2018 the European Space Agency’s XMM-Newton X-ray satellite was able to finally re-observe the black hole and to scientists’ amazement the same repeated heartbeat could still be seen.

Model for the Quasi-Periodic Oscillations (QPO) — or ‘heartbeat’ — where the inner part of the accretion disc is oscillating in size and shape, shown as a cross-section in the plane of the disc. Credit: Dr. Chichuan Jin of the National Astronomical Observatories, Chinese Academy of Sciences

Matter falling on to a supermassive black hole, as it feeds from its surroundings, releases an enormous amount of power from a comparatively tiny region of space, but this is rarely seen as a specific repeatable pattern like a heartbeat. The time between beats can tell us about the size and structure of the matter close to the black hole’s event horizon. The heartbeat also proves that such signals arising from a supermassive black hole can be very strong and persistent. Scientists are further planning to execute a comprehensive analysis of this intriguing signal. They will then compare it with the behavior of stellar-mass black holes in our Milky Way.

Image credit Dr Chichuan Jin and NASA/Goddard Space Flight Center Conceptual Image Lab. Source: Durham University

The research, by the National Astronomical Observatories, Chinese Academy of Sciences, China, and Durham University, UK, appears in the journal Monthly Notices of the Royal Astronomical Society as “Reobserving the NLS1 galaxy RE J1034+396 – I. The long-term, recurrent X-ray QPO with a high significance” by Chichuan Jin, Chris Done and Martin Ward, 10 June 2020.
DOI: 10.1093/mnras/staa1356