Astronomers have discovered what may be the brightest object in the universe, a quasar with a black hole at its heart growing so fast that it swallows the equivalent of a sun a day.
In a few billion years, our aging Sun will run out of hydrogen fuel in its core and begin to swell, eventually engulfing Mercury, Venus, and probably Earth itself. Known as the red giant phase, this is a normal step in a mid-sized star’s life cycle, when it swells to hundreds of times its usual size. There are plenty of red giants in the night sky, but astronomers have never caught one in the act of swallowing its planets — until now.