Black holes are among the most mysterious cosmic objects, much studied but not fully understood. In pursuit of understanding these celestial bodies, astronomers have stumbled upon a supermassive black hole, located a whopping 12.9 billion light-years from Earth, and it’s doing something pretty spectacular. The “blazar” is firing a super-powerful beam of energy straight towards us.

The energy beam from this black hole has travelled to us, just over 100 million years after the Big Bang took place — setting a new record for the distance from which we’ve observed such a phenomenon. The discovery also raises questions about how supermassive black holes grow so rapidly in the Universe’s infancy.

Named J0410-0139, the black hole has a mass of about 700 million Suns and is one of the oldest of its kind that scientists have ever observed. Detected using data from several telescopes, including NASA’s Chandra Observatory and Chile’s Very Large Telescope, the black hole has provided a new peek into the early universe.

“The alignment of J0410-0139’s jet with our line of sight allows astronomers to peer directly into the heart of this cosmic powerhouse. This blazar offers a unique laboratory to study the interplay between jets, black holes, and their environments during one of the Universe’s most transformative epochs,” said Dr Emmanuel Momjian, an astronomer at the National Radio Astronomy Observatory in Virginia, associated with the study, published in The Astrophysical Journal Letters.

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What is a blazar?

The universe is full of powerful supermassive black holes that create powerful jets of high-energy particles, creating sources of extreme brightness in the vastness of space. When one of those jets points directly at Earth, scientists call the black hole system a blazar, as per NASA.

The jets extending from these blazars can extend millions of light-years in length. They are exceedingly bright because as particles approach the speed of light, they give off a tremendous amount of energy and behave in weird ways that Albert Einstein predicted.

Up until now, a little less than 3,000 blazars have been discovered but most are located closer to Earth than J0410-0139. Despite decades of study, scientists still don’t fully grasp the physical processes that shape the dynamics and emission of blazar jets.

At the centre of the Milky Way is a supermassive black hole called Sagittarius A*. It is roughly 27,000 light years from Earth and 23.5 million kilometres in diameter.

In a world first, a team of astronomers led by Florian Peißker from the University of Cologne, Germany, have discovered a binary star system orbiting this black hole.

The system is known as D9. Its discovery, announced in a new paper published today in Nature Communications, sheds light on the extreme environment at the centre of our Milky Way galaxy.

It also helps explain a long-running cosmic mystery about why some stars hurtle through space much faster than others.

What Is A Binary Star System?

A binary star system is simply two stars orbiting each other.

Our Sun is not part of a binary, which is a good thing: we wouldn’t want another star wandering through our Solar System. It would disrupt the orbit of the Earth; we’d fry or freeze.

Observations show about two thirds of the stars in the Milky Way are single stars, and the remainder are part of a binary or multiple star system. Larger stars are more likely to be paired.

Binary star systems are useful to astronomers because their motion contains a wealth of information. For example, the speed and distance of the orbits tell us about the masses of the stars.

For a single star, by contrast, we usually work out its mass from how bright it is.

A Technically Challenging Discovery

Although scientists have previously predicted that binary star systems exist near supermassive black holes, they have never actually detected one.

This recent discovery was technically quite challenging. We can’t simply look at the system and see two stars, because it’s too far away. Rather, the astronomers used the European Southern Observatory’s Very Large Telescope to measure the shifting of the starlight – known as the Doppler effect. This showed that the stellar system’s light had a characteristic wobble, indicating an orbit.

But the team did much more than that.

Because binary stars contain a wealth of information, the astronomers could calculate that this particular system is approximately 2.7 million years old. That is, 2.7 million years ago, these stars first ignited.

They probably weren’t born in the black hole’s extreme surroundings, so unless they only recently wandered into this neighbourhood, they have lasted about a million years in their current environment.

This, in turn, tells us about the black hole’s ability to disrupt stars in its orbit. Black holes are mysterious beasts, but clues such as this are helping us unravel their nature.

Circling A Black Hole

The situation the astronomers discovered is quite familiar.

Think of the Moon: it orbits the Earth, and the Earth and the Moon together orbit the Sun. Because gravity is an attractive force, it can pull multiple celestial objects into complicated orbits. The complexity of this scenario inspired the recent book and Netflix series, The Three Body Problem.

If they are complicated, could the whole thing drift apart? The Moon–Earth–Sun arrangement is stable because two of the three bodies – the Earth and Moon – are much closer together than the other body, the Sun. The Moon and Earth are close enough that, so far as the Sun is concerned, it’s effectively a two-body system, which is stable.

But if all three bodies interact, the system can come apart. It is even possible for two of the bodies to eject the third body entirely.

Stars Of Unusual Speed

This mechanism probably explains a cosmic mystery: hypervelocity stars.

Most stars in the night sky are in a typical, almost-circular orbit around the centre of our galaxy. Orbital speeds are about 200 kilometres per second: very fast on Earth, but nothing special in space.

However, since 2005 we have discovered about 20 hypervelocity stars, which are hurtling through our galaxy at more than 1,000 kilometres per second. How?

Our best current idea is that hypervelocity stars were once part of a binary system orbiting our supermassive black hole. In time, the stars got too close to the black hole, and a complicated orbit resulted. In the kerfuffle, with a black hole calling the shots, one of the stars got ejected. It escaped to the outer Milky Way, where we see it as a hypervelocity star.

Finding The Hypervelocity Factory

It’s an interesting theory.

Theoretical calculations show the mechanism works and the speeds are about right. Observations show many of the known hypervelocity stars appear to be shooting away from the galactic centre, which is another plus for the theory. But how else could we test this idea?

An obvious way is to look for binary stars around our supermassive black hole.

Astronomers have been keeping a close eye on our galactic centre for decades. It’s not too difficult to find in the night sky, as you can see from the image below.

Here are two reliable methods to find Sagittarius A*. First, find Antares (bright and red), which is the centre of the back of Scorpio, and then follow the scorpion’s body to the tip of the tail, and that’s close-ish to the black hole. Alternatively, get a good night sky app on your phone; they’re amazing.

In the context of these theories, this recent discovery is very important. Astronomers found a binary star system around our supermassive black hole. An important piece of the hypervelocity puzzle falls into place.

(Author: Luke Barnes, Lecturer in Physics, Western Sydney University)

(Disclosure Statement: Luke Barnes does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment)

This article is republished from The Conversation under a Creative Commons license. Read the original article.
 

US space agency NASA has recorded an eerie audio clip that captures sound waves coming out of a supermassive black hole situated 250 million light years away. The acoustic waves, coming out of the black hole located at the heart of the Perseus cluster of galaxies, were transposed up 57 and 58 octaves to make them audible for human ears.

The audio was released in 2022 and it was the first time when the sound waves were extracted and made audible.

Sound waves do exist in space, even though we might not be able to hear them naturally.

In a surprising discovery in 2003, astronomers detected acoustic waves rippling out through the huge amounts of gas surrounding the supermassive black hole at the Perseus galaxy cluster, which is now popular for its eerie wails.

It is difficult to hear them at their current pitch as it includes the lowest note ever detected in the universe by humans – much below the limits of human hearing.

NASA’s recent sonification has majorly amplified these sound waves, in order to get a sense of how they would sound like while ringing through the intergalactic space.

The lowest note, which was identified in 2003, is a B-flat and is located over 57 octaves below middle C, the report said, adding that its frequency is 10 million years at that pitch.

It is to be noted that the lowest note that can be detected by human ears has a frequency of one-twentieth of a second.

After being extracted radically from the supermassive black hole, these sound waves were played in an anti-clockwise direction from the center. 

This was done to make them audible in all directions from the supermassive black hole at the enhanced pitches of 144 quadrillion and 288 quadrillion higher then their original frequency.

Like several other waves recorded from space, the result for this one was eerie too. 

The tenuous gas and plasma, which drifts between the galaxies, in clusters known as the ‘intracluster medium’ is denser and much hotter than the intergalactic medium outside it. As the temperatures help to regulate star formation, hence sound waves could play a pivotal role in galaxy clusters’ evolution over longer periods.

This artist’s concept shows a galaxy with a brilliant quasar, a very bright, distant and active supermassive black hole that is millions to billions of times the mass of the Sun, at its center, seen in this undated handout picture.
| Photo Credit: Reuters

Two mighty beams of energy have been detected shooting in opposite directions from a supermassive black hole inside a distant galaxy – the largest such jets ever spotted, extending about 140 times the diameter of our vast Milky Way galaxy.

The black hole resides at the heart of a galaxy about 7.5 billion light-years from Earth. A light-year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). Because of the time it takes for light to travel, looking across great distances is peering back in time, with these observations dating to when the universe was less than half its current age.

Black holes are extraordinarily dense objects with gravity so strong that not even light can escape. Most galaxies, including the Milky Way, have a large black hole at their core. Some of these shoot jets of high-energy particles and magnetic fields into space from their two poles as they devour material such as gas, dust and stars falling into them due to their immense gravitational strength.

The two jet structures documented in the new study – using the LOFAR (Low-Frequency Array) radio telescope, a network of antennas centered in the Netherlands – extend 23 million light-years from end to end.

These super-heated jets, caused by the violent events around the black hole, are comprised of subatomic particles called electrons and positrons, and magnetic fields, moving at nearly the speed of light.

The researchers have nicknamed these two jets Porphyrion (pronounced poor-FEER-ee-ahn), named after a giant from ancient Greek mythology. Porphyrion is about 30% longer than the previous record-holder for such jets.

“Jet systems like Porphyrion appear to be among the most energetic spectacles that have occurred in the universe since the Big Bang,” said Caltech astrophysicist Martijn Oei, lead author of the study published in the journal Nature, referring to the event that initiated the universe about 13.8 billion years ago.

“The general understanding is that jets are formed when magnetized material falls onto a rotating black hole,” added astrophysicist and study co-author Martin Hardcastle of the University of Hertfordshire in England. “They need to be sustained by a continued infall of matter into the black hole, something of the order of one solar mass (the mass of the sun) a year of material.”

Such jets, not visible to the naked eye, start out small and grow over time.

“We’ve known for a while that black holes can generate these jets. But what is interesting is that to generate a large structure like this, the jets must stay on for a long time – about a billion years,” Hardcastle said.

The Porphyrion jets reach far beyond their home galaxy, with an energetic output equivalent to trillions of stars like the sun.

“That is equivalent to the energy released during the most cataclysmic cosmic collisions: for example, those that occur when two galaxy clusters, each sometimes containing thousands of galaxies, merge together,” Oei said.

“The fact that it extends so far from its parent black hole means that it may be carrying energy, particles and magnetic fields into the voids in the cosmic web, the gaps between groups and filaments of galaxies which we know make up the large-scale structure of the universe. This may help us to understand the ubiquitous magnetic fields in the present-day universe,” Hardcastle said.

Such jets could heat up gas in interstellar space, shutting down the formation of new stars that requires cold clouds of gas, and could damage habitable planets, the researchers said.

The Milky Way’s supermassive black hole, in its current quiescent state, does not have such jets.

“The key finding is that jets from black holes can, if circumstances are right, become as large as the universe’s major cosmic structures – galaxy clusters, cosmic filaments, cosmic voids,” Oei said. “This means that individual black holes can have a sphere of influence that extends way beyond the galaxy in which they reside.”

The Indian Space Research Organisation’s (ISRO) AstroSat’s full multi-wavelength capabilities have enabled an international team of scientists to unravel the mysteries surrounding the X-ray binary system MAXI J1820+070, hosting a black hole.

AstroSat is India’s first multi-wavelength space observatory which was launched in September 2015 and now a comprehensive study presents unique insights into the behaviour of this transient black hole X-ray binary during its 2018 outburst.

According to ISRO, MAXI J1820+070, positioned around 9800 light-years distant from Earth, is a transient black hole X-ray binary.

It was first detected during its outburst in 2018 using the MAXI instrument aboard the International Space Station (ISS). Because of its proximity to Earth and its remarkable brightness upon discovery, emerging as the second brightest object in the X-ray sky, MAXI J1820+070 garnered significant attention within the astronomy community.

AstroSat, equipped with three X-ray payloads and a UV telescope, captured soft and hard X-ray emissions and far ultraviolet radiation, painting a detailed portrait of the near and distant regions surrounding the black hole in MAXI J1820+070.

Prof. Dipankar Bhattacharya, chairperson of the AstroSat Science Working Group and a co-author of this study, said “This is the first time the full capability of all the co-pointed instruments in AstroSat have been used in unison, supplemented by ground-based observations, and the results are fascinating. I am happy to be a part of this unique investigation of one of the most interesting Black Hole sources discovered in recent times”.

The space agency further said that the significance of this study extends beyond MAXI J1820+070, highlighting the pivotal role of AstroSat in advancing the understanding of transient black hole X-ray binaries.

“With its unique multi-wavelength capabilities, AstroSat opens doors to further exploration of diverse astrophysical phenomena, laying the groundwork for future endeavours in the field,” the space agency said.

Scientists have no reported evidence of the true conditions in Hell, perhaps because no one has ever returned to tell the tale. Hell has been imagined as a supremely uncomfortable place, hot and hostile to bodily forms of human life.

Thanks to a huge astronomical survey of the entire sky, we have now found what may be the most hellish place in the universe.

In a new paper in Nature Astronomy, we describe a black hole surrounded by the largest and brightest disc of captive matter ever discovered. The object, called J0529-4351, is therefore also the brightest object found so far in the universe.

Supermassive black holes

Astronomers have already found around one million fast-growing supermassive black holes across the universe, the kind that sit at the centres of galaxies and are as massive as millions or billions of Suns.

To grow rapidly, they pull stars and gas clouds out of stable orbits and drag them into a ring of orbiting material called an accretion disc. Once there, very little material escapes; the disc is a mere holding pattern for material that will soon be devoured by the black hole.

The disc is heated by friction as the material in it rubs together. Pack in enough material and the glow of the heat gets so bright that it outshines thousands of galaxies and makes the black hole’s feeding frenzy visible to us on Earth, more than 12 billion light years away.

The fastest-growing black hole in the universe

The accretion disc of J0529-4351 emits light that is 500 trillion times more intense than that of our Sun. Such a staggering amount of energy can only be released if the black hole eats about a Sun worth of material every day.

It must also have a large mass already. Our data indicate J0529-4351 is 15 to 20 billion times the mass of our Sun.

There is no need to be afraid of such black holes. The light from this monster has taken more than 12 billion years to reach us, which means it would have stopped growing long ago.

In the nearby universe, we see that supermassive black holes these days are mostly sleeping giants.

Black holes losing their grip

The age of the black hole feeding frenzy is over because the gas floating around in galaxies has mostly been turned into stars. And after billions of years the stars have sorted themselves into orderly patterns: they are mostly on long, neat orbits around the black holes that sleep in the cores of their galaxies.

Even if a star dove suddenly down towards the black hole, it would most likely carry out a slingshot manoeuvre and escape again in a different direction.

Space probes use slingshot manoeuvres like this to get a boost from Jupiter to access hard-to-reach parts of the Solar System. But imagine if space were more crowded, and our probe ran into one coming the other way: the two would crash together and explode into a cloud of debris that would rapidly fall into Jupiter’s atmosphere.

Such collisions between stars were commonplace in the disorder of the young universe, and black holes were the early beneficiaries of the chaos.

Accretion discs – a no-go zone for space travellers

Accretion discs are gateways to a place whence nothing returns, but they are also profoundly unfriendly to life in themselves. They are like giant storm cells, whose clouds glow at temperatures reaching several tens of thousands of degrees Celsius.

The clouds are moving faster and faster as we get closer to the hole, and speeds can reach 100,000 kilometres per second. They move as far in a second as the Earth moves in an hour.

The disc around J0529-4351 is seven light years across. That is one and a half times the distance from the Sun to its nearest neighbour, Alpha Centauri.

Why only now?

If this is the brightest thing in the universe, why has it only been spotted now? In short, it’s because the universe is full of glowing black holes.

The world’s telescopes produce so much data that astronomers use sophisticated machine learning tools to sift through it all. Machine learning, by its nature, tends to find things that are similar to what has been found before.

This makes machine learning excellent at finding run-of-the-mill accretion discs around black holes – roughly a million have been detected so far – but not so good at spotting rare outliers like J0529-4351. In 2015, a Chinese team almost missed a remarkably fast-growing black hole picked out by an algorithm because it seemed too extreme to be real.

In our recent work, we were aiming to find all the most extreme objects, the most luminous and most rapidly growing black holes, so we avoided using machine learning tools that were guided by too much prior knowledge. Instead we used more old-fashioned methods to search through new data covering the entire sky, with excellent results.

Our work also depended on Australia’s current 10-year partnership with the European Southern Observatory, an organisation funded by several European countries with a huge array of astronomical facilities.

The interaction between a supermassive black hole in a galaxy named 2MASX J02301709+2836050 and a star orbiting it is seen in this image captured by the Pan-STARRS telescope, in Hawaii, U.S., in an undated handout image provided by NASA.
| Photo Credit: Reuters

Black holes, celestial objects known for their gluttony, usually eat stars unlucky enough to stray too close to them in one big gulp, annihilating them with their enormous gravitational pull. But some, it turns out, tend to snack rather than gorge.

Researchers said they have observed a supermassive black hole at the center of a relatively nearby galaxy as it takes bites out of a star similar in size and composition to our sun, consuming material equal to about three times Earth’s mass each time the star makes a close pass on its elongated oval-shaped obit.

Black holes are extraordinarily dense objects with gravity so strong that not even light can escape.

The star is located about 520 million light years from our solar system. A light year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km). It was observed being plundered by a supermassive black hole at the heart of a spiral-shaped galaxy.

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As such black holes go, this one is relatively small, estimated to have a mass a few hundred thousand times larger than the sun. The supermassive black hole at the center of our galaxy, called Sagittarius A*, possesses about 4 million times the mass of our sun. Some other galaxies harbor supermassive black holes hundreds of millions times the mass of the sun.

Most galaxies have such black holes at their center, and the environment around them can be among the most violent places in the universe.

Most of the data used by the scientists in the new study came from NASA’s orbiting Neil Gehrels Swift Observatory.

The star was observed orbiting the black hole every 20 to 30 days. At one end of its orbit, it ventures near enough to the black hole to have some material from its stellar atmosphere sucked away, or accreted, each time it passes – but not so close as to have the whole star shredded. Such an event is called a “repeating partial tidal disruption.”

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The stellar material that falls into the black hole heats up to around 3.6 million degrees Fahrenheit (2 million degrees Celsius), unleashing an immense amount of X-rays. Those were detected by the space observatory.

“What’s most likely to happen is the star’s orbit will gradually decay and it will get closer and closer to the supermassive black hole until it gets close enough to be completely disrupted,” said astrophysicist Rob Eyles-Ferris of the University of Leicester in England, one of the authors of the study published this week in the journal Nature Astronomy.

“That process is likely to take years at least – more likely decades or centuries,” Eyles-Ferris added.

This marked the first time that scientists had observed a sun-like star being repeatedly snacked upon by a supermassive black hole.

“There are lots of unanswered questions about tidal disruption events and exactly how the orbit of the star affects them,” Eyles-Ferris said. “It’s a very fast-moving field at the moment. This one has shown us that new discoveries could come at any time.”