The birth of the biggest black holes ever seen: NASA spots blazar galaxies from just 1.4 billion years after the Big Bang

NASA's Fermi Gamma-ray Space Telescope found the gamma-ray blazars
Experts say they could shed fresh light on how black holes form

Published: 20:13 EST, 30 January 2017 | Updated: 20:17 EST, 30 January 2017

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The are the biggest black holes ever seen - and could help explain how the mysterious astronomical phenomenons form.

NASA's Fermi Gamma-ray Space Telescope has identified the farthest gamma-ray blazars, a type of galaxy whose intense emissions are powered by supersized black holes.

Light from the most distant object began its journey to us when the universe was 1.4 billion years old, or nearly 10 percent of its present age, and experts say they could shed fresh light on how black holes form.

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Black-hole-powered galaxies called blazars are the most common sources detected by NASA's Fermi. As matter falls toward the supermassive black hole at the galaxy's center, some of it is accelerated outward at nearly the speed of light along jets pointed in opposite directions. When one of the jets happens to be aimed in the direction of Earth, as illustrated here, the galaxy appears especially bright and is classified as a blazar.

WHAT IS A BLAZAR

A blazar is a very compact quasar with a supermassive black hole at the center of an active, giant elliptical galaxy.

Blazars are among the most energetic phenomena in the universe.

The name 'blazar' was originally coined in 1978 by astronomer Edward Spiegel to denote the combination of these two classes.

'Despite their youth, these far-flung blazars host some of the most massive black holes known,' said Roopesh Ojha, an astronomer at NASA's Goddard Space Flight Center in Maryland.

'That they developed so early in cosmic history challenges current ideas of how supermassive black holes form and grow, and we want to find more of these objects to help us better understand the process.'

A blazar is a very compact quasar with a supermassive black hole at the center of an active, giant elliptical galaxy, and are among the most energetic phenomena in the universe.

Researchers revealed the findings Monday, Jan. 30, at the American Physical Society meeting in Washington, and a paper describing the results has been submitted to The Astrophysical Journal Letters.

They constitute roughly half of the gamma-ray sources detected by Fermi's Large Area Telescope (LAT).

Astronomers think their high-energy emissions are powered by matter heated and torn apart as it falls from a storage, or accretion, disk toward a supermassive black hole with a million or more times the sun's mass.

A small part of this infalling material becomes redirected into a pair of particle jets, which blast outward in opposite directions at nearly the speed of light.

Blazars appear bright in all forms of light, including gamma rays, the highest-energy light, when one of the jets happens to point almost directly toward us.

More distant blazars show a loss of higher-energy gamma rays thanks to the extragalactic background light (EBL), a 'cosmic fog' of visible and ultraviolet starlight that permeates the universe. From studies of nearby blazars, scientists know how many gamma rays should be emitted at different energies. If a gamma ray on its way to Earth collides with lower-energy light in the EBL, it converts into a pair of particles and is lost to astronomers. As shown by the graphs at left in this illustration, the more distant the blazar, the fewer high-energy gamma rays we can detect.

Previously, the most distant blazars detected by Fermi emitted their light when the universe was about 2.1 billion years old.

Researchers began by searching for the most distant sources in a catalog of 1.4 million quasars, a galaxy class closely related to blazars.

Because only the brightest sources can be detected at great cosmic distances, they then eliminated all but the brightest objects at radio wavelengths from the list.

With a final sample of about 1,100 objects, the scientists then examined LAT data for all of them, resulting in the detection of five new gamma-ray blazars.

A blazar is a very compact quasar with a supermassive black hole at the center of an active, giant elliptical galaxy.

Expressed in terms of redshift, astronomers' preferred measure of the deep cosmos, the new blazars range from redshift 3.3 to 4.31, which means the light we now detect from them started on its way when the universe was between 1.9 and 1.4 billion years old, respectively.

'Once we found these sources, we collected all the available multiwavelength data on them and derived properties like the black hole mass, the accretion disk luminosity, and the jet power,' said Vaidehi Paliya of Clemson University in South Carolina.

Two of the blazars boast black holes of a billion solar masses or more.

All of the objects possess extremely luminous accretion disks that emit more than two trillion times the energy output of our sun.

This means matter is continuously falling inward, corralled into a disk and heated before making the final plunge to the black hole.

'The main question now is how these huge black holes could have formed in such a young universe,' said Gasparrini.

'We don't know what mechanisms triggered their rapid development.'

In the meantime, the team plans to continue a deep search for additional examples.

'We think Fermi has detected just the tip of the iceberg, the first examples of a galaxy population that previously has not been detected in gamma rays,' said Ajello.