For the two decades before 2019, the galaxy was the same level of faintness in the night sky.
The teams research isaccepted for publicationin Astronomy & Astrophysics.
The galaxy is SDSS1335+0728 (and thats just its nicknameseriously!).
An animation of the galaxy spinning and brightening over recent years.Gif:ESO/M. Kornmesser
The team has yet to conduct follow-up observations to clarify the nature of the event.
If it is a tidal disruption, its the longest and faintest yet seen.
News from the future, delivered to your present.
An illustration of the galaxy’s accretion disc, a supermassive black hole at its center.Illustration:ESO/M. Kornmesser