QSO J0529−4351 (SMSS J052915.80–435152.0) is a quasar, 12 billion light-years away in the Pictor constellation, notable for being the most luminous object ever observed at roughly 500 trillion times the luminosity of the Sun.

In a Gaia DR3 data set published on 13 June 2022, QSO J0529−4351 was assigned a 99.98% probability of being a star in the Milky Way via an automated analysis.

[2] An automated analysis of 2022 data from the European Space Agency's Gaia satellite did not confirm J0529-4351 as too bright to be a quasar, and suggested it was a 16th magnitude star with a 99.98% probability.

However, discovering that this was the brightest quasar ever observed required a larger telescope—the X-shooter spectrograph on the European Southern Observatory's VLT in Chile's Atacama Desert.

We discovered an object whose true essence was not immediately recognized, although it literally looked into our eyes for many years, because it was shining brightly, most likely even before the birth of man.