Buzz
No other cosmic entity compares to the bizarre nature of a black hole. Even the brightest scholars have difficulty explaining why conventional physics breaks down around them or what occurs inside these all-consuming behemoths.
Each year, this mysterious phenomenon unveils strange and unsettling evidence about its true nature. Time reversal, black holes from a deceased universe, and the first sighting of forces even more powerful than black holes are just a few of the newest revelations.
10. Abundance of IMBHs
Midsize black holes are the enigmatic middle child of the cosmic family. They are neither as numerous as the stellar-mass black holes nor as immense as the supermassive ones. Known as IMBHs (intermediate-mass black holes), they are so rare that some researchers believe they might be absent altogether.
In 2018, the elusive hiding spots of IMBHs were uncovered. For reasons still unclear, these black holes tend to dwell at the heart of small galaxies. Once scientists pinpointed where to search, these rare black holes were found in swarms.
Typically, a supermassive black hole sits at the center of a star cluster. This rule began to weaken as more dwarf galaxies were discovered revolving around IMBHs. However, as their numbers rise, the likelihood of solving an associated mystery increases as well.
Scientists have yet to explain how certain supermassive black holes emerged so quickly after the Big Bang. So far, the insights gained from IMBHs support existing theories about the formation of supermassive black holes—they either grow from IMBHs or arise when vast gas clouds collapse. While this doesn’t completely resolve the puzzle, it does confirm that scientists are on the right track.
9. Enigmatic Objects Close to Sagittarius A*
Sagittarius A* is the supermassive black hole located at the heart of our galaxy. In the early 2000s, two mysterious objects were found orbiting around it. Referred to as G-class objects, they resembled gas clouds and were expected to be destroyed as they neared their closest approach to Sagittarius A*. However, when they survived, the true mystery began to unfold.
Gas clouds aren’t supposed to survive such close encounters with a supermassive black hole. In 2018, researchers identified three more objects orbiting closely around Sagittarius A*. Although data from the past 12 years couldn’t definitively classify them as G-class objects, it’s highly likely they are. They appear fluffy like gas clouds, but exhibit characteristics of extremely massive stars.
This was precisely the conclusion scientists reached about the first two objects that survived—they were probably stars. Stars in orbit around a black hole may sound strange, but the situation becomes even more bizarre.
At one time, they were part of a binary system (two stars orbiting one another). However, the immense gravity of Sagittarius A* caused them to violently merge, adopting a swollen shape that led scientists to mistakenly identify them as gas clouds. The mystery remains unresolved. The differing orbits of the objects suggest they may have different origins.
8. The Oldest Black Hole
The discovery of the universe's most ancient black hole goes beyond just its age. This cosmic relic could provide answers to enduring questions about the era when the first stars were born.
Discovered in 2017, this supermassive black hole formed just 690 million years after the big bang. At a time when the universe was only 5 percent of its current age, this black hole already had a mass 800 million times that of the Sun.
ULAS J1342+0928 lies approximately 13.1 billion light-years from Earth and was formed during the early stages of the universe. This period, known as the 'epoch of reionization,' marked the time when the first stars emerged from ions and gravity. The exact cause of reionization is still a mystery, but black holes are considered a potential factor.
Moreover, no one can explain how black holes could have grown so massive in the early universe. ULAS J1342+0928 may offer insights into these questions, but more black holes from this era are needed to draw definitive conclusions. Unfortunately, black holes from this time are extremely scarce.
7. The Fastest-Growing Black Hole
In 2018, the hungriest black hole set a new record. With an appetite that devours the equivalent of the Sun every two days, it holds the title of the fastest-growing black hole. Fortunately, it is located far from us. If it were at the center of the Milky Way, its X-rays would annihilate all life on Earth.
When scientists observed the first flash, they were witnessing light emitted 12 billion years ago. Once confirmed to be from a black hole, its immense mass quickly became clear—approximately 20 billion times that of the Sun. The reason for its rapid expansion remains a mystery to researchers.
The only known aspect of its growth makes this black hole far from black. Due to the vast amounts of gas it pulls in, the resulting friction and heat could easily outshine an entire galaxy. In fact, it could shine thousands of times brighter. If this cosmic oddity were located at the center of the Milky Way, humans would be left seeing nothing but a handful of stars.
6. A Hidden Galaxy
A galaxy cluster can contain hundreds or even thousands of galaxies. These clusters are regarded as some of the largest structures in the universe. It may seem impossible for a single cosmic object to hide an entire cluster, but that's exactly what one quasar managed to do.
This supermassive black hole, identified as PKS1353-341, was originally thought to be a solitary object in its region. However, in 2018, MIT scientists revealed a photo that exposed the truth. The quasar was actually located at the center of a galaxy cluster. Its brilliance was so intense that it overwhelmed the light of millions of stars. No other galaxy has been obscured in such a way.
Situated approximately 2.4 billion light-years from Earth, the quasar's dazzling light is likely the result of a feeding frenzy. It is believed that PKS1353-341 devours matter at an astonishing rate, emitting energy 46 billion times brighter than the Sun. Astronomers predict it will calm down in about a million years.
5. Binary Systems
Another intriguing aspect of black holes is their existence in binary systems, where two black holes orbit each other. This can be a perilous scenario. To date, three instances of black hole collisions have been recorded—two in 2015 and one in 2017.
Remarkably, the signal from this event was a series of gravitational ripples caused by a brief collision that took place three billion light-years away. Rather than being destroyed, the two black holes merged into one larger black hole, surpassing the size of both of its parents.
This third merger was a significant breakthrough for scientists. Not only did it offer another rare observation, but it also helped confirm a new field of study focused on gravitational waves.
Regarding the formation of binary black holes, researchers suggest two possible scenarios. One possibility is that binary stars perish and leave behind black holes. Alternatively, the black holes may have formed independently and later drifted toward one another, eventually becoming gravitationally bound.
4. A Cataclysmic Earth-Destroying Bubble
In 2018, physicists proposed an additional way that black holes could, in theory, bring about the end of Earth. This came shortly after the scientific community celebrated the discovery of gravitational waves—a phenomenon that stretches and compresses the very fabric of reality. It may sound absurd, but it is also a deadly force.
The new theory envisioned gravitational waves emanating from a high-energy collision event, expanding as a bubble. Spreading at light speed, it enlarges, and some points grow flat. If two such bubbles collide at one of these flat points, the worst-case scenario predicts that space-time would likely condense into a black hole.
If this were to occur near Earth, it would be disastrous. On the upside, if that could be considered an upside, no one would meet a strange end inside the new black hole. Instead, the gravitational waves causing its formation would stretch the planet apart first.
3. Specters From Universes That Have Faded Away
In 2018, a provocative physicist made an extraordinary claim. Roger Penrose, already causing a stir among neuroscientists with his assertion that human consciousness arises from quantum computing, now posited that our universe is merely the latest in an ongoing series. More specifically, Penrose suggested that black holes from dead universes could be detected in the one that exists today.
This hypothesis relies on the concept of Hawking radiation. Stephen Hawking famously proposed that black holes eventually decay after shedding enough particles. Known as gravitons and photons, these particles are massless and do not experience conventional time or speed.
Consequently, when a universe perishes and another emerges, proponents of this theory argue that these particles persist. The detected remnants are Hawking radiation—energy released as black holes gradually dissolve in long-gone universes.
Experimental results have bolstered Penrose and his supporters, prompting them to advocate for a revision of the big bang theory. If their claims are accurate, rather than a single cataclysmic explosion creating one cosmos, universes would succeed one another like rising bubbles.
2. The Concept of Time Reversal
A black hole forms when a massive star collapses in on itself after its life ends. In the process, it releases intense bursts of gamma rays, which are the most luminous force observed in nature, though their full nature remains a mystery.
In 2018, a strange phenomenon emerged from these signals—they seemed to reverse time. Scientists uncovered this when they examined the six most powerful gamma-ray bursts ever recorded by NASA. Each event emitted a light wave with a unique pulse sequence. In an odd twist, the gamma ray's pulse sequence was then repeated in reverse.
This might not seem strange at first, but nothing behaves normally near a black hole. For some physicists, this reversed signal suggests the possibility of time reversal. However, the underlying cause remains completely unknown.
Other theories propose a more physical explanation. The gamma ray might be passing through dense clumps of matter, creating the observed signature. To reverse it, the beam might be striking an unknown reflective surface or behaving in ways that defy current physical laws.
1. A Banished Black Hole
For years, scientists speculated that galaxies might expel their central black holes. Yet, there had been no evidence to support this. That was until 2017, when the galaxy 3C186 delivered an unexpected discovery.
Originally the result of a merger between two galaxies, 3C186 was expected to appear chaotic. Surprisingly, it was well-structured and orderly. The true shock came when scientists looked for the typical supermassive black hole at the center—and found nothing.
When they located it, the black hole was found 35,000 light-years from the center. During the collision of the two star clusters, their supermassive centers fused, creating an immense black hole. The merger likely released powerful gravitational waves that were strong enough to expel the black hole.
This was no easy task. To push the black hole away, a burst of energy equivalent to 100 million supernovas was required. Whatever the cause, it revealed forces more powerful than the usual gravitational dominance black holes have over their territories.
The colossal entity continues to accelerate at an astonishing rate. At its current velocity, it could break free from the galaxy and venture into open space within 20 million years.
