The Quiet Death of a Star
In 2014, astronomers spotted a massive yellow star in the Andromeda galaxy. By 2022, it had vanished without a trace — without the usual blinding explosion of a supernova. It was as if someone simply switched off the light.
Black Hole's Heartbeat Steadies
At the heart of galaxy 1ES 1927+654, a black hole behaves like a lighthouse with a faulty mechanism. Every six and a half minutes, it releases a burst of X-ray light, a rhythm astronomers have been tracking since 2022. At first, the beacon's tempo wandered — speeding up and slowing down, with intervals ranging from one beat every eighteen minutes to one every seven.
Lightning over a black hole: the first Neupert effect beyond our Galaxy
Active galactic nuclei (AGN) are the universe’s powerhouses: their X-ray coronae blaze millions of times hotter than stellar atmospheres. But what strikes the spark? A ten-day X-ray campaign by the XRISM and XMM-Newton satellites, aimed at NGC 3783, provided the answer: it’s actual thunderstorms.
Dusty Echoes of Torn Stars in Active Galactic Nuclei
In active galactic nuclei, supermassive black holes are surrounded by a dense ring of dust that acts like a curtain: it hides everything happening at the center. If a star ventures too close to the black hole, tidal forces tear it apart, and the resulting flare is usually visible in optical and X-ray light.