Distant, Luminous Quasar

Astronomers using the United Kingdom Infrared Telescope (UKIRT) in Hawaii have observed a luminous quasar (ULAS J112001.48+064124.3) at a redshift of z~7.085. This places the quasar in a period around 770 million years after the big bang. Analysis of the light curve suggests the core is super massive balck hole of around 2 billion solar masses.

The findings, reported in the journal Nature, present theorists with some serious questions as to how such a massive object came into being so early in the universe. Was it the result of a series of stellar evolutions and accretions onto a star of half a million solar masses, or did a super massive cloud of gas simply collpase into to form the black hole and skip the stellar evolution phase?

In addition to the conundrum over its mass, the quasars exists in an era where there is a transition in the nature of the inter-galactic medium (IGM). By using the quasar as a background light source it is possible to evaluate, amongst other things, the fraction of neutral-hydrogen in the IGM at this time. By comparing the abundances with IGM around other quasars at a redshift of z=6 it is possible to understand how the IGM evolved. This will help place constraints on the physical processes involved in the early universe.

The initial obseravation with UKIRT was followed up with observations using the Liverpool Telescope, Gemini North and the Very Large Telescope (Antu) and it is likely that further observations will follow due to the significance of the result.

Astronomers estimate that there are only around 100 such objects in the entire sky - so it might be some years before further similar objects are discovered and a consistent scientific pattern emerges.