Every big galaxy has a supermassive black hole at its center, but scientists are still trying to fully understand how these black holes and their galaxies are connected.
Stephen DiKerby, a research associate in physics and astronomy, recently had a thrilling moment when he spotted X-rays from a black hole flickering on and off.
It felt like seeing a cosmic heartbeat in action.
Supermassive black holes are some of the strangest and most powerful objects in the universe.
They pack millions or even billions of times the Sun’s mass into a tiny area, creating gravity so strong that not even light can escape.
But even though we can’t see them directly, we can detect the hot material swirling around them through X-rays, thanks to space telescopes like the Chandra X-ray Observatory.
DiKerby and his team, including his supervisor Shuo Zhang, studied 15 years of X-ray data from Chandra, focusing on the supermassive black hole in the nearby Andromeda galaxy, called M31* (M31 star).
Their work is helping scientists understand how black holes and galaxies have shaped the universe over billions of years.
Their findings were published in The Astrophysical Journal.
This research originally grew out of the study of neutrinos — tiny, fast-moving particles that could be linked to the extreme environments around black holes.
DiKerby, who is also part of the IceCube Neutrino Observatory team, wanted to see if M31* could be one of these neutrino sources.
Using Chandra’s incredible ability to zoom in with fine detail, the researchers separated the X-rays coming from M31* from nearby sources that crowd around the center of Andromeda.
They discovered that M31* had a major X-ray flare in 2006, which was followed by another flare in 2013. Since 2006, the black hole has stayed in a more active state.
This behavior is similar to what IceCube recently observed with another galaxy, linking black hole flares to bursts of neutrino activity. Studying these flares helps scientists better predict when and where neutrinos might be released.
To track M31*, DiKerby’s team had to carefully measure X-rays from four nearby objects, an incredibly delicate task he compared to trying to see four flickering candles from across a football stadium.
Their work depends on the Chandra telescope, which, despite still working well, faces threats of being shut down due to funding cuts. DiKerby hopes people realize how important it is to keep Chandra running and to invest in future telescopes like AXIS, which won’t be ready until the 2030s.
He says the story of M31* isn’t finished yet. He hopes scientists will keep watching and recording the history of supermassive black holes, using tools like Chandra while we still can.
