Astronomers Detect Ancient Quasar Glowing from the Early Universe

An early-universe quasar, the earliest of its kind to date, has been found flickering by astronomers from Columbia University, the Massachusetts Institute of Technology, and others. The findings were reported in Nature Astronomy.

Every galaxy, including the Milky Way, has a supermassive black hole in its center. When a black hole is active, it pulls material toward it as a whirlpool of hot gas and dust. This cosmic material radiates a tremendous amount of energy as it accumulates and crashes onto the black hole, illuminating the surrounding area.

Quasars are, simply put, the most energetic supermassive black holes, and some of the universe’s most active and bright objects. These systems consume so much matter that the energy they release can be more than all of the light in the galaxy. Scientists can learn more about how active supermassive black holes shape the galaxies around them by examining a quasar's light pattern.

A recently discovered quasar dates back to the “cosmic dawn,” which occurred 850 million years after the Big Bang; put another way, when the universe was only 850 million years old, this quasar was already mature. It is the earliest flickering quasar discovered so far.

Flickering caused by gas falling into a supermassive black hole is one of the best ways to study the mechanisms by which black holes grow in size, yet this has been nearly impossible to do so far for the youngest quasars found in the early universe.

Kishalay De, Assistant Professor, Astronomy, Columbia University

“Although there have been a lot of quasars found in the cosmic dawn, this is the first time we actually see one flickering,” added Gene Leung, a postdoc in the MIT Kavli Institute for Astrophysics and Space Research.

The quasar’s flicker allowed the researchers to discover that, astonishingly, the ancient quasar’s whirlpool of gas and dust, known as an accretion disk, resembled a flat pancake, similar in shape to modern-day quasars.

Their discoveries contribute to a long-standing cosmic conundrum: Why do supermassive black holes appear so early in the universe's history? Physicists believed that a flat accretion disk represents a relatively mature black hole in a stable and tranquil condition.

Newly formed black holes, such as those in the early cosmos, should be more unstable systems with more puffy and disordered accretion disks. The flat accretion disk seen around this extremely early quasar adds to the riddle of how supermassive black holes can form and mature in such a brief period of cosmic time.

I think what this suggests is that all the messy, very rapid growth phases that we expect all black holes to go through at some point happen very, very early on, before we see them as these very bright luminous quasars. That’s the picture that’s emerging.

Anna-Christina Eilers, Assistant Professor, Physics, Massachusetts Institute of Technology

The flicker was found in data obtained by NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) project, a space-based infrared telescope that examined the whole sky for around 14 years. As a former MIT postdoc, De made the effort to reprocess this archive data.

Following this finding, the team intends to go even further back in cosmic time to observe a quasar’s early development. Then, scientists may begin to piece together the circumstances that produced the first supermassive black holes.

This study was supported in part by NASA.

The NEOWISE data [has] opened up an entirely new field of studying quasar variability in the early universe, and sets the benchmark for similar large-scale studies that will soon be possible with upcoming ground and space-based infrared survey telescopes.

Kishalay De, Assistant Professor, Astronomy, Columbia University