Tag: astronomy

New Theory Suggests We’ve Been Wrong About Black Holes for 60 Years

How confusing inevitability with reality built decades of paradox.

What if general relativity never actually tells us that black holes already exist, but only that their formation is inevitable in an infinite future we can never observe? In a new theory, Daryl Janzen, a physicist at the University of Saskatchewan in Saskatoon, Canada, questions whether we’ve mistaken mathematical inevitability for physical reality, and shows how much of our black hole story rests on that quiet leap.

Black holes are among the most captivating and scientifically intriguing phenomena in modern physics, inspiring both scientists and the public alike.

But do they really exist? What if they are only ever forming, never formed?

Just imagine — what if the whole edifice of black hole physics is built on an invalid logical inference that’s gone unnoticed (or unacknowledged?) for the better part of a century?

Inevitability is not actuality — that’s obvious enough. Yet for sixty years physicists have ignored relativity’s most basic rule, and we’ve taken for granted that the latter is implied by the former. Like fools walking around imagining we’re all dead because someday we’ll die, they look at the evidence that nothing can stop black holes from collapsing toward their horizons and imagine that a process which remains forever incomplete has already come to its end.

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Astronomers Say They Just Detected Radio Signals Coming from This Comet

Evidently, it’s a big week for news involving comets, as a team of astronomers now reports the detection of an intriguing series of radio signals emanating from one of the speeding objects (no, not that comet) currently making its way through our solar system.

The surprising news comes to us courtesy of a research team led by the Shanghai Astronomical Observatory of the Chinese Academy of Sciences, and was reportedly made possible with the Tianma Radio Telescope.

During multi-band radio observations of comet 12P/Pons-Brooks, the team detected an interesting series of radio signals coming from the returning comet, which is also one of the brightest comets astronomers have ever seen.

At a glance, this all sounds pretty tantalizing… but what does the detection of radio signals from a comet in our solar system actually mean?

A Returning Comet Stops In

First discovered in 1812, 12P/Pons-Brooks possesses an orbital period of around 71 years, meaning that this is actually the fourth time astronomers have had an opportunity to watch it during its journeys through the solar system.

During their recent observations of the Halley-type comet, the Chinese team says they measured the rate at which water was being produced by 12P/Pons-Brooks, which revealed the most distant known detection of ammonia molecules known to astronomers from such observations.

Since comets are known to contain a variety of icy components—many of which are as old as the solar system itself—they are ideal for observations by astronomers, particularly when these materials begin to bake off as the speeding objects make their way toward the Sun.

In the case of comets like 12P/Pons-Brooks, the presence of volatile ices shows that they haven’t been subjected to large amounts of thermal evolution since they were born in our solar system eons ago. Because of this, the study of the ices they carry and their composition offers a way for astronomers to look back in time at the chemical and thermal conditions that were present in our planetary neighborhood around 4.6 billion years ago.

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Interstellar Object Is Spraying Something Weird, Scientists Find

A new analysis of our solar system’s interstellar interloper, 3I/ATLAS, reveals that it’s spewing huge amounts of water — and astronomers can’t immediately explain why.

The object, which is widely believed to be comet, showed strong ultraviolet emissions that are unmistakable telltales of hydroxyl gas (OH), a byproduct of water, when astronomers imaged it with NASA’s Neil Gehrels Swift space telescope before it disappeared behind the Sun. The emissions could only be spotted from space because the ultraviolet light would get absorbed in the atmosphere.

Their findings, detailed in a new study published in The Astrophysical Journal Letters, argue that the presence of all this OH indicates the comet is ejecting water vapor at a torrential rate of about 88 pounds per second — around the same rate as a fire hose running at full blast, according to a press release about the findings.

The most extraordinary thing is that this was spotted happening pretty far from the Sun, at a heliocentric distance of about three astronomical units (AU) away, or three times the distance between the Earth and our star. Typically, comets stray much closer to the Sun before the water ice in their core, called a nucleus, begins to sublimate, or instantly transform from a solid to a gas. Something else must be driving all the water dumping from 3I/ATLAS — which also implies, tantalizingly, that the comet must harbor considerable stores of water for this process to keep going.

“When we detect water — or even its faint ultraviolet echo, OH, — from an interstellar comet, we’re reading a note from another planetary system,” coauthor Dennis Bodewits, a professor of physics at Auburn University, said in the release. “It tells us that the ingredients for life’s chemistry are not unique to our own.”

It’s another example of the fascinating strangeness of interstellar objects like 3I/ATLAS. Think of it as a sample of somewhere very far away, perhaps tens of millions of light years, careening straight past our doorstep. That it’s in many ways bizarre compared to local comets hints at just how unique these unimaginable alien realms must be, and how we have so much more to understand of how star systems form and how their structures may evolve.

Typically, a comet’s coma, a huge halo of gas and dust that give comets their glowing appearance, begin to form as the object nears the Sun — or another star, presumably — and heats up. The heat either sublimates or vaporizes the material in its nucleus, which is many times smaller than the tail that catches our eyes from the ground, stretching behind the comet.

3I/ATLAS’s coma has already surprised us in many ways. Its chemistry is strange compared to our own comets, and it appears to have an astonishingly high ratio of carbon dioxide to water.

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Was the “Wow! Signal” Emitted from 3I/ATLAS?

The “Wow! Signal” was detected on August 15, 1977 as a strong narrowband radio signal by Ohio State University’s Big Ear radio telescope. Its origin was inferred to be extraterrestrial. The latest natural explanation (accessible here) hypothesized that the “Wow! Signal” was caused by a sudden brightening of the hydrogen line emitted from an interstellar cloud, triggered by a strong transient radio source, such as a flare from a highly magnetized neutron star (magnetar).

The “Wow! Signal” originated from the sky coordinates of Right Ascension (RA)=19h25m=291 degrees and Declination (Dec)=-27 degrees.

On August 12, 1977, the interstellar object 3I/ATLAS was at a distance of about 600 times the Earth-Sun separation (AU) — corresponding to a light-travel time of about 3 days. It had the sky coordinates of RA=19h40m=295 degrees and Dec=-19 degrees. These parameters can be inferred accurately given the lack of non-gravitational acceleration for 3I/ATLAS, as inferred in my latest paper (accessible here).

Hence, the “Wow! Signal” was separated by approximately 4 degrees in RA and 8 degrees in Dec from the direction of 3I/ATLAS. The chance of two random directions in the sky being aligned to that level is about 0.6 percent. If the “Wow! Signal” originated from 3I/ATLAS, how powerful was the transmitter?

The detected intensity of the “Wow! Signal” was in the range of 54–212 Jansky with a bandwidth of about 10 kilohertz. At the distance of 600 AU, this corresponds to a source power of 0.5–2 gigawatts, the output of a typical nuclear reactor on Earth.

The “Wow! Signal” was observed at a frequency of 1420.4556±0.005 megahertz, blue-shifted by about 10 kilometers per second towards Earth relative to the central frequency of the hydrogen line. This blueshift is of the same order of magnitude but smaller than expected from the approach velocity of 3I/ATLAS towards the Sun, 60 kilometers per second.

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Astronomers uncover a hidden world on the solar system’s edge

A small team led by Sihao Cheng, Martin A. and Helen Chooljian Member in the Institute for Advanced Study’s School of Natural Sciences, has discovered an extraordinary trans-Neptunian object (TNO), named 2017 OF201, at the edge of our solar system.

The TNO is potentially large enough to qualify as a dwarf planet, the same category as the much more well-known Pluto. The new object is one of the most distant visible objects in our solar system and, significantly, suggests that the empty section of space thought to exist beyond Neptune in the Kuiper Belt is not, in fact, empty at all.

Cheng made the discovery alongside colleagues Jiaxuan Li and Eritas Yang from Princeton University, using advanced computational methods to identify the object’s distinctive trajectory pattern on the sky. The new object was officially announced by the International Astronomical Union’s Minor Planet Center and in an arXiv pre-print.

Trans-Neptunian objects are minor planets that orbit the Sun at a greater average distance than the orbit of Neptune. The new TNO is special for two reasons: its extreme orbit and its large size.

“The object’s aphelion — the farthest point on the orbit from the Sun — is more than 1600 times that of the Earth’s orbit,” explains Cheng. “Meanwhile, its perihelion — the closest point on its orbit to the Sun — is 44.5 times that of the Earth’s orbit, similar to Pluto’s orbit.”

This extreme orbit, which takes the object approximately 25,000 years to complete, suggests a complex history of gravitational interactions. “It must have experienced close encounters with a giant planet, causing it to be ejected to a wide orbit,” says Yang. “There may have been more than one step in its migration. It’s possible that this object was first ejected to the Oort cloud, the most distant region in our solar system, which is home to many comets, and then sent back,” Cheng adds.

“Many extreme TNOs have orbits that appear to cluster in specific orientations, but 2017 OF201 deviates from this,” says Li. This clustering has been interpreted as indirect evidence for the existence of another planet in the solar system, Planet X or Planet Nine, which could be gravitationally shepherding these objects into their observed patterns. The existence of 2017 OF201 as an outlier to such clustering could potentially challenge this hypothesis.

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Mysterious Object Hurtling Toward Us From Beyond Solar System Appears to Be Emitting Its Own Light, Scientists Find

Last month, astronomers made an exciting discovery, observing an interstellar object — only the third ever observed — hurtling toward the center of the solar system.

The object, dubbed 3I/ATLAS, has caught the attention of Harvard astronomer Avi Loeb, who has a long track record of making controversial predictions about previous interstellar objects being relics from an extraterrestrial civilization.

While there’s been a growing consensus among astronomers that the latest object is a comet, Loeb has continued to entertain the idea that it may have been sent to us by an intelligent species from outside of the solar system — and he’s far from backing down.

In a blog post over the weekend, Loeb pointed to observations by NASA’s Hubble Space Telescope, which showed a “glow of light, likely from a coma, ahead of the motion of 3I/ATLAS towards the Sun.”

A coma is the hazy and luminous cloud that surrounds the nucleus of a comet.

However, there’s “no evidence for a bright cometary tail in the opposite direction,” he wrote, with scientists suggesting it was evidence that dust was evaporating from the object’s Sun-facing side.

The observations led Loeb and his colleagues to an intriguing, albeit far-fetched possibility: is the mysterious space object generating “its own light?”

After deliberations with his colleague and Harvard astrophysicist Eric Keto, Loeb suggested that the “simplest interpretation” of 3I/ATLAS’ observed “steep brightness profile” is that its nucleus “produces most of the light.”

That would also mean that its actual size is much smaller than currently thought, roughly in line with the size of the first two interstellar objects we’ve observed, ‘Oumuamua and 2I/Borisov.

The Harvard astronomer suggested two possibilities: either 3I/ATLAS is naturally emitting radiation because its a “rare fragment from the core of a nearby supernova that is rich in radioactive material” — or it’s a “spacecraft powered by nuclear energy, and the dust emitted from its frontal surface might be from dirt that accumulated on its surface during its interstellar travel.”

Loeb deemed the former explanation “highly unlikely,” and the latter as requiring “better evidence to be viable.”

Loeb previously argued that the object’s unusual trajectory — which includes suspiciously close flybys of both Earth and Jupiter — and its lack of a visible tail both undermine the theory that it’s a comet.

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Astronomers say new interstellar visitor 3I/ATLAS is ‘very likely to be the oldest comet we have ever seen’

The recently discovered interstellar visitor 3I/ATLAS may be one of the oldest comets ever seen by humanity.

The object was already exciting to astronomers as only the third space object seen entering the solar system from beyond its limits, the other two being 1I/’Oumuamua seen in 2017 and 2I/Borisov detected in 2019.

However, new research has shown this potentially “water ice-rich” visitor could be even more extraordinary than initially believed. 3I/ATLAS could be around 3 billion years older than our 4.5 billion-year-old solar system and thus any comet ever before observed.

University of Oxford astronomer Matthew Hopkins is part of a team of scientists that think 3I/ATLAS, discovered on July 1, 2025 by the ATLAS survey telescope, is around 7 billion years old.

“All non-interstellar comets, such as Halley’s comet, formed at the same time as our solar system, so they are up to 4.5 billion years old,” Hopkins said in a statement. “But interstellar visitors have the potential to be far older, and of those known about so far, our statistical method suggests that 3I/ATLAS is very likely to be the oldest comet we have ever seen.”

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NASA confirms that mysterious object shooting through the solar system is an ‘interstellar visitor’ — and it has a new name

NASA scientists have confirmed that a mysterious object shooting toward us through the solar system is an “interstellar object” — only the third of its kind ever seen. Experts have also given the cosmic interloper an official name, and revealed new information about its origins and trajectory.

News of the extrasolar entity, initially dubbed A11pl3Z, broke on Tuesday (July 1), when NASA and the International Astronomical Union (IAU) both listed it as a confirmed object. It was first discovered in data collected between June 25 and June 29 by the Asteroid Terrestrial-impact Last Alert System (ATLAS), which automatically scans the night sky using telescopes in Hawaii, Chile and South Africa. Multiple telescopes across the world have subsequently spotted the object in observation data that date back to June 14.

The object is traveling toward the sun extremely fast, at around 152,000 mph (245,000 km/h), and observations suggest that it is set on an extremely flat and straight trajectory, unlike anything else in the solar system. This led many experts to speculate that it originated from beyond the sun’s gravitational influence and has enough momentum to shoot straight through our cosmic neighborhood without slowing down.

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Planetary Defenders Track Fast-Moving “Interstellar Object” Through Solar System

On Wednesday, the European Space Agency revealed that its Planetary Defenders are tracking a fast-moving “interstellar object” zipping through the solar system. While some might hope it’s an alien spacecraft—finally giving Paul Krugman a win—chances are it’s just another space rock. 

“Astronomers may have just discovered the third interstellar object passing through the Solar System!” ESA said, adding, “ESA’s Planetary Defenders are observing the object, provisionally known as A11pl3Z, right now using telescopes around the world.” 

It’s still unclear whether A11pl3Z is a rocky asteroid, an icy comet, or something else entirely. Its size and shape also remain unknown. NASA has confirmed it is actively tracking the object, while astronomers say more observations are needed to determine its origin. 

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Astronomers baffled by mystery object flashing signals at Earth every 44 minutes: ‘Like nothing we’ve ever seen’

The truth is out there.

Astronomers say they’re stunned by an unidentified object flashing strange signals from deep space.

The object, named ASKAP J1832-0911, was detected by the Australian Square Kilometre Array Pathfinder (ASKAP) and NASA’S Chandra X-ray observatory — the world’s most powerful X-ray telescope.

“It is unlike anything we have seen before,” Andy Wang, an astronomer at Curtin University in Perth, Australia, declared in a statement published this week.

ASKAP J1832-0911 emits pulses of radio waves and X-rays for two minutes every 44 minutes, according to the experts, who documented their findings in Nature journal.

ASKAP J1832-0911 has been classified as a “long-period transient” or “LPT” — a cosmic body that emits radio pulses separated by a few minutes or a few hours.

Wang and his team theorize that the object could be a dead star, but they don’t know why it “switches on” and “switches off” at “long, regular and unusual intervals,” Space.com reports.

“ASKAP J1831-0911 could be a magnetar (the core of a dead star with powerful magnetic fields), or it could be a pair of stars in a binary system where one of the two is a highly magnetised white dwarf (a low-mass star at the end of its evolution),” Wang wrote.

“However, even those theories do not fully explain what we are observing,” he added. “This discovery could indicate a new type of physics or new models of stellar evolution.”

Wang and his team hope to detect similar another using radio waves and the Chandra X-ray observatory, saying a subsequent discovery will help them learn more about the nature of such LPTs

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