A team of American and Dutch physicists has discovered the earliest and most distant active galactic nucleus. The result has important implications for the early history of the universe. Astronomers currently believe that super-massive black holes form at the centre of galaxies. However, in the early universe there would not have been enough time for such black holes to form according to existing models of galaxy formation. The new results suggest instead that primordial black holes - formed at the beginning of the universe - may have merged together to form a proto-galactic nucleus. These proto-nuclei would have gradually attracted enough gas and dust to form the early galaxies. TN J0924-2201 – at 9 percent the age of the universe and - is a prime candidate to confirm this theory (The Astrophysical Journal June 20).
Wil van Breugel from the Lawrence Livermore Laboratory and colleagues from the University of California, Berkeley and Leiden Observatory in the Netherlands found their galactic nucleus by looking for radio sources that generate strong radio waves over a narrow band from a single power source. They looked for optical candidates of these sources at near infrared wavelengths using the Keck II telescope. This allowed them to measure the redshift of the objects. The galaxy at TN J0924-2201 was measured at a redshift of 5.19 – further than any known quasar source. This overturns the idea that quasars are the most distant radio sources in the universe.
Earlier this year the Hubble Space Telescope pinpointed the most distant galaxy at ultraviolet wavelengths at a redshift of 6.68 – 5% the present age of the universe.
