eROSITA discovers a 'changing-look' Seyfert galaxy

Astronomers have tracked a dramatic "changing-look" active galactic nucleus (AGN) whose central supermassive black hole appeared to switch off and then rapidly reignite. The galaxy, HE 1237−2252, dimmed in X-rays by a factor ...

NASA missions track record-breaking radio burst from sun

When NASA scientists first observed a particular radio burst from the sun in August 2025, there was nothing unusual about it. But then the radio burst kept going. Typically, solar radio bursts like these last a few hours ...

One graph attempts to connect every object in the universe

If you've ever taken an introductory astronomy class, you've probably seen the Hertzsprung-Russell (HR) diagram. This graph maps out the life cycle of stars by plotting their temperature against their luminosity, and has ...

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