The quasar monster: The most hellish place in the universe

There's no need to fear such black holes. They aren't just far away, but they stopped growing a long time ago.

Pep Boatella

Quasars are luminous objects powered by supermassive black holes that have revolutionised our understanding of the universe.

The quasar monster: The most hellish place in the universe

Mohammed Mansour

last update on 02 Mar 2024

About 61 years ago, while analysing the spectrum of a distant star, the Dutch-born American astronomer Maarten Schmidt saw unusual lines, brightness, and glitter recorded by American astronomical observatories.

The scientist reviewed the data he obtained, thinking his eyes were fooling him. The ambiguous lines, however, remained the same.

Schmidt sent several letters to other observatories to confirm the data, only to realise months later that he had discovered something completely new.

One year later, in 1964, the Taiwanese-born American scientist Hong-Yee Chiu coined a term to describe the distant and luminous objects Schmidt discovered. The term now widely known for pseudo-stars is “quasars”.

This groundbreaking discovery revolutionised our understanding of the universe by revealing the presence of incredibly distant and luminous objects supported by supermassive black holes.

Since their discovery, quasars have been the subject of extensive studies about different wavelengths of light. This has contributed significantly to our knowledge of cosmology, galaxies, and the physics of black holes.

According to the journal Nature, astronomers believe they may have found the brightest object in the universe. The quasar draws its energy from a black hole that grows so fast that it swallows the equivalent of the sun's mass every day.

The quasar's accretion disk, which scientists call J0529-4351, emits light 500 trillion times stronger than sunlight.

The data show that the black hole that feeds that distant quasar is 15 to 20 billion times the sun's mass and is about 12 billion light-years away from Earth.

AFP — An image published by the European Observatory (ESO), depicting the shape of the record-breaking quasar star, February 21, 2024.

What are quasars?

A quasar is an astrophysical phenomenon characterised by the presence of a stunningly luminous and active object in the centres of distant galaxies, supported by the accumulation of matter onto a supermassive black hole.

These objects emit radiation across the electromagnetic spectrum, from radio waves to X-rays and gamma rays, with a luminosity beyond the brightness of entire galaxies.

They are thought to represent an active stage in the evolution of galaxies, where the gravitational energy of the incident matter generates intense heat and radiation, creating a bright star-like appearance.

Christian Wolf, an astronomy researcher at the Australian National University, who’s the lead author of the study, says that the quasar itself is a “fast-growing black hole".

Speaking to Al Majalla, he says what makes the black hole visible to scientists “is the growth that devours everything around it.”

If a black hole stops growing, “it’s impossible to see it because it doesn’t reflect light at all". But when the black hole grows, the matter that it devours is sucked in.

The phenomenon is called the accretion disk, which is “a pattern of cohesion in which matter rotates around the black hole closer to it until it’s swallowed by it.”

As the material rotates, a great amount of heat is produced, making black holes “shine brighter than galaxies. That brilliance appears in quasars, Wolf said.

Quasars have significantly contributed to our knowledge of cosmology, galaxies, and the physics of black holes.

The importance of quasar studies lies in the fact that most large galaxies have a huge black hole at their centre, which greatly affects the evolution of their host galaxies.

But there's no need to fear such black holes. The "monster" isn't just far away, but it stopped growing a long time ago.

This means the new quasar's light, which travels at a speed of 300,000 kilometres per second, will take more than 12 billion years to reach us.

For now, this monster is "asleep", says Wolf.

It signals the end of its mass-feeding age when most of the gas in galaxies turned into stars. Billions of years later, those stars came together in orderly patterns to orbit neatly around sleeping black holes at the core of galaxies.

The brightest place in the universe

This new quasar illuminates as much as 500 trillion suns or 20,000 times the brightness of the entire Milky Way. It's the brightest object now known in the universe. Its images date back to when black holes were most active.

Astronomers already know that there are a million fast-growing supermassive black holes in the universe — the kind found in the centres of galaxies and as massive as millions or billions of suns.

To grow rapidly, they need to pull stars and gas clouds from their stable orbits into their accretion disks.

A disk heats up by friction with enough material, and the heat glow becomes so bright that it outperforms thousands of galaxies and makes the black hole's activity visible.

The newly-found quasar grows at its maximum growth rate, known as the Eddington Limit; this is the maximum luminosity a celestial body can reach before the radiation pressure emitted by the light becomes so intense that it overcomes the force of gravity.

AFP — An image published by the Nature Publishing Group shows how a rare tidal disturbance and energy release occurs as a star is torn apart by a massive black hole, November 30, 2022.

It's not a fixed number but increases with the mass of the black hole itself. So, if the black hole continues to grow at the Eddington Limit, its mass will grow exponentially, doubling every 30 million years.

But why hasn't this quasar been discovered before?

The most extreme black holes are extremely rare. Wolf says his science group has examined almost everything in the sky that looks like a quasar.

"Millions of less voracious black holes, which feed on one Sun a month, are still waiting to be discovered, but our work focuses on aggressive black holes that eat one Sun a day," he says.

A bright discovery

The European Southern Observatory spotted this object, J0529-4351, during a 1980 sky survey, but it was thought to be a star.

It wasn't identified as a "quasar" until last year after observations made by telescopes in Australia and Chile's Atacama Desert settled the matter.

In a telescope-taken image of the sky, the quasars look just like stars.

"The first quasar was discovered 61 years ago because it was a powerful radioactive source that appeared to coincide with another star."

But the number of stars far outnumbers that of quasars. So, we need information that distinguishes between the two types and reveals the quasar needle in the straw pile of stars.

Millions of less voracious black holes, which feed on one Sun a month, are still waiting to be discovered, but our work focuses on aggressive black holes that eat one Sun a day.

Christian Wolf, astronomy researcher

Recently, excellent data has been available from two space missions that surveyed the entire sky. The European Space Agency's Gaia Observatory accurately measured the motions of a billion stars, almost all of them in the Milky Way.

This data helps our understanding of their flow patterns and history. Some are stars in distant parts of the galaxy that are too far away to distinguish any motion, so a few are not stars at all but "quasars."

In that study, the researchers used data on medium infrared colours from NASA's Wide-Field Infrared Survey Explorer.

In medium infrared, the colours of stars tend to differ from those of quasars because stars have a single-temperature surface. In contrast, the bright part of the quasar contains a mixture of temperatures with changing colours.

When the researchers combined the two sets of space data together — Gaia's and NASA's — they proved the data to be strong enough to allow for finding almost all quasars with few errors among the celestial bodies they chose to study in detail.

The quasars of the early universe

There appear to be black holes found in the early universe – half a billion years after the Big Bang – that are too massive to have formed from the remnants of a star that collapsed early and then "simply" grew to what they are.

Most of the time, Wolf says, "we thought that black holes formed in galaxies, first from the collapse of massive stars, and then they grew over time."

PICTURE

Now, that study raises more and more questions about whether black holes came first and even served as seeds for galaxies to form around them.

"It'll be exciting over the coming decades to do more research into this," Wolf says.

The most infernal place in the universe

"This new quasar is the most violent place we know of in the universe," he explains.

The quasar's visible accretion disk width is seven light-years and is one and a half times the distance from the solar system to the nearest star, Alpha Centauri.

That accretion disk is like a giant hurricane with a black hole in the eye of a storm, with wind speeds ranging from thousands of kilometres per second on the outer edge to 10,700 kilometres per second on the interior.

The disk is unimaginably hot, at thousands of degrees Celsius. The entire storm is connected by strong magnetic fields, and there is cosmic lightning everywhere. This is an important source of heat in the whirlwind.

"I tend to describe it as the biggest hell gates we've found anywhere in the universe because if you personally fall into the accretion disk, you'll end up completely black and, of course, you won't come back," Wolf said.

"We now found the most infernal place in the universe."

+ / -