Abell 2744-QSO1 (abbreviated as QSO1) is a 50-million-stellar-mass supermassive black hole (technically an active galactic nucleus) traveling through space almost by itself, [3] located approximately 13 billion years ago in the epoch of re-ionisation [3] behind the galaxy cluster Abell 2744. [4] It is surrounded by a very small galaxy, with very tight upper limits on its stellar mass; [5] the matter surrounding it comprises mostly hydrogen and helium, with very few of the heavier elements which are created by stars, etc. [6] For this reason it is likely that the black hole formed before the galaxy, rather than the other way round, contradicting the traditional idea that black holes formed from the merging of stars in already-formed galaxies. [3] It has been called a "naked" black hole: [3] cosmologist Robert Maolino has described it as "really challenging for the theories." [7]
First observed by the James Webb Space Telescope (under the aegis of the UNCOVER programme) in 2023, [8] QSO1 is in the class of little red dots, a class of small red cosmological objects discovered by the JWST over its first few years whose general nature is actively debated. [3] Located behind Pandora's Cluster in the constellation Sculptor, it is the most distant gravitationally lensed object imaged to date, [9] and is triply imaged by the cluster's gravity. [10] It is the first of the little red dots to have its mass directly measured (through observations of the vortex surrounding it), confirming the effectiveness of indirect mass measurements based on the whole object's spectrum for other little red dots. [3]
QSO1 is one of the first supermassive black holes directly confirmed not to follow the textbook origin story for black holes (slow formation in a galaxy), which struggles to effectively explain the quick formation of supermassive black holes in the universe anyways. [3] Hypotheses for its formation include it being a primordial black hole, formed from density irregularities after the Big Bang; a "not-quite-primordial" black hole formed from a dense spot after the Big Bang that collapsed several hundred thousand years later; or having formed very quickly in a galaxy after all through a special formation method, followed by the rest of the galaxy quickly disappearing. [3]
Although quasars of this type were predicted in theory by Stephen Hawking, it presents a both a challenge to and an opportunity for cosmology, [11] and has been bruited as the "missing link" [10] between black hole seeds [12] and the first luminous quasars. [13] Some scientists hypothesize it may have grown from primordial black hole seeds formed in the first fraction of a second after the Big Bang, or created as a direct collapse black hole. [7] [14]
