Scratching the edge of the Universe: the most distant Blazar yet!

Scientists have detected an ancient super-massive black hole with the name PSO J030947.49+271757.31. Its distance was calculated 13 billion light-years from Earth making it officially the most distant blazar ever observed with a relativistic jet pointing directly toward Earth.

An artist’s impression of a blazar. Image credit: DESY / Science Communication Lab.

The vast majority of galaxies (including our own Milky Way) host a super-massive black hole in their center that may have mass of millions or even billions of Suns. In some of those galaxies, there are hungry black holes surrounded by a disk of hot gas and dust while they consume matter. This process produce large amounts of energy making the centers of these galaxies very bright. This class of galaxies are called Active Galactic NucleiSome of these Active Galactic Nuclei further create colossal jets of material that travel close to the speed of light (quasars). Though, when a galaxy happens to be oriented so the jets point toward our Solar system — and we actually look directly to black holes — it’s called a blazar. It’s the same thing as a quasar, just pointed at a different angle. Blazars are among the most luminous objects known in the Universe and they are very bright in all forms of light, including the most energetic light, the gamma-rays.

A research team, led by Silvia Belladitta, a Ph.D. student at the University of Insubria, working for the Italian National Institute for Astrophysics (INAF) in Milan, under the supervision of Alberto Moretti and Alessandro Caccianiga, was able to determine that it is the oldest to be discovered based on wavelength signatures of the black hole’s redshift – the longer a wavelength, the more red it appears which can provide a clue to the age. PSO J0309+27 was first detected in data from the NRAO VLA Sky Survey and the Panoramic Survey Telescope and Rapid Response System PS1 databases. The discovery was confirmed using the X-Ray Telescope (XRT) on board NASA’s Neil Gehrels Swift Observatory and the Multi-Double Object Spectrographs (MODS) at the Large Binocular Telescope (LBT).

S. Belladitta said: “The spectrum that appeared before our eyes confirmed first that PSO J0309+27 is actually an active galaxy nucleus, or a galaxy whose central nucleus is extremely bright due to the presence in its centre of a supermassive black hole fed by the gas and the stars it engulfs. In addition, the data obtained by the Large Binocular Telescope (LBT) also confirmed that PSO J0309+27 is really far away from us, according to the shift of the colour of its light toward red or redshift with a record value of 6.1, never measured before for a similar object.

According to the study, this blazar likely formed just 900 million years after the Big Bang. This means the discovery can help understand better the early cosmos. Ms Belladitta said: “Observing a blazar is extremely important. For every discovered source of this type, we know that there must be 100 similar, but most are oriented differently, and are therefore too weak to be seen directly. Thanks to our discovery, we are able to say that in the first billion years of life of the Universe, there existed a large number of very massive black holes emitting powerful relativistic jets. This result places tight constraints on the theoretical models that try to explain the origin of these huge black holes in our Universe.

This work was published in March 06 in the Astronomy & Astrophysics journal with the title: “The first blazar observed at z > 6” with first author Silvia Belladitta. The paper can be found in: