Astronomers have found the most distant blazar to date, revealing important new details about ancient black holes, and the early evolution of the universe, reports phys.org.
RELATED: WHAT HAPPENS INSIDE A BLACK HOLE?
Blazars are supermassive black holes
A supermassive black hole actively feeding on its host galaxy, this blazar exists in a part of the universe that's 13 billion light-years away, from a time when the universe was only 1 billion years old.
While its status — as the farthest-known blazar in existence — is easy to remember, its name is not: PSO J030947.49+271757.31, or PSO J0309+27 for short, the ancient black hole was discovered by a team of researchers at the Univesity of Insubria, working for the Italian National Institute for Astrophysics (INAF) in Milan, under supervision of Alberto Moretti and Alessandro Caccianiga.
Italian astronomers unveil the ancient universe
The team, led by Ph.D. student Silvia Belladitta at the University of Insubria, suspected the object was very distant, and observations from the Swift Space Telescope showed that the object's X-ray power signature matched that of other blazars.
Observations made via the optical Multi-Double Object Spectrographs (MODS) at the Large Binocular Telescope (LBT) confirmed the object's identity as the new record-smashing ancient blazar; the farthest in the known universe.
Blazars feed within the brightest classes of cosmic objects, called active galactic nuclei (AGN) — supermassive black holes (SMBHs) churning and consuming maddeningly away at the centers of galaxies. Astronomers can tell whether or not they're active by the presence of a disk or sphere of ionized gas surrounding them — fuel for emissions that stretch out many times the size of the black hole itself into the reaches of intergalactic space.
Ancient black holes: fortuitous find, difficult study
These powerful relativistic jets are so bright they can be seen across the universe, 13 billion light-years away, 13 billion years later. However, a blazar beam is only observable along a narrow line of sight, which makes the detection of such an object not only fortuitous but also immensely difficult. More importantly, this blazar is one of the earliest, most distant SMBHs ever seen that isn't obscured by dust (most AGNs are).
This means astronomers were able to study the ancient black hole across the complete electromagnetic spectrum, and build a comprehensive image of its properties.
"The spectrum that appeared before our eyes confirmed first that PSO J0308+27 is actually an AGN, or a galaxy whose central nucleus is extremely bright due to the presence in its center of a supermassive black hole fed by the gas and the stars it engulfs," said the first author of the paper on the discovery, published Monday in the journal Astronomy & Astrophysics. "In addition, the data obtained by LBT also confirmed that PSO J0209+27 is really far away from us, according to the shift of color of its light toward red or redshift with a record value of 6.1, never measured before for a similar object."
As more advanced land and space-based telescopes are put to work for an increasingly-networked astronomical community, we can be sure to find more record-breaking discoveries like this blazar. Moreover, the study of ancient black holes will play a key role in our understanding of how the physical universe evolved into the one we live in now.