Tag Archives: disappearance

The Mysterious Disappearance of a Star: Insights into a Failed Supernova Explosion

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Illustration of a failed supernova creating a black hole

Illustration of a Failed Supernova Explosion Forming a Black Hole

NASA, ESA, and P. Jeffries (STScI)

A massive star in the Andromeda galaxy has seemingly vanished instead of exploding, resulting in the formation of a black hole in a peculiar manner.

Typically, black holes originate from stars that explode as supernovas. However, they can also emerge from stars that collapse due to their own gravity, directly creating black holes without the explosive phase.

In 2024, Kisharai De from Columbia University, along with his team, investigated the case of M31-2014-DS1, an exceptionally bright star located in the Andromeda galaxy, approximately 20 times the mass of our Sun. The star exhibited an initial brightening in 2014, followed by a significant dimming from 2017 to 2020. This behavior aligned with predictions for a supernova that would fail to result in a black hole, yet no direct evidence of the black hole was observed, such as X-ray emissions.

Currently, De and his colleagues are utilizing the James Webb Space Telescope (JWST) and Chandra X-ray Observatory to study M31-2014-DS1. They have detected a faint red object at the star’s previous location, which is only about 8% brighter than the original star and enveloped in rapidly expanding dust. This finding aligns with the expected characteristics of a supernova that fails to produce a black hole. However, De and his team have refrained from commenting further, as their research has not yet undergone peer review.

Another group studying the same JWST data, including Emma Beasor from Liverpool John Moores University, UK, suggested that the case for M31-2014-DS1 failing to explode may also indicate a stellar merger, which could result in small explosions followed by dimming and dust formation.

“Predictions for the appearance of a failed supernova significantly overlap with what we might expect from a collision of two stars creating vast amounts of dust,” Beasor explained.

However, both scenarios are rare, she noted, as it is uncommon to observe such drastic color changes in a star.

“No matter the explanation, it’s fascinating that the visible star has essentially vanished,” stated Gerald Gilmore from Cambridge University. “For years, the search for extinct massive stars has produced ambiguous outcomes, but now, advancements in multi-wavelength time-domain astronomy are paving the way for clarity.”

The definitive method for confirming black hole formation is through the identification of X-ray emissions, Gilmore noted, which are currently absent at the M31-2014-DS1 location. Nevertheless, if advanced telescopes like JWST can analyze the remnants of dimmed stars, we could soon uncover what occurred. “We are on the verge of discovering at least one of the ultimate fates of a massive star, which is intriguingly akin to the Cheshire Cat’s disappearance,” he remarked.

References: arXiv, DOI: 10.48550/arXiv.2601.05774 and DOI: 10.48550/arXiv.2601.05317

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Source: www.newscientist.com

Study Reveals Disappearance of Dark Matter as Cause for Excess Galactic Centers in the Milky Way

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The galactic center excess refers to an unexpected intensity of gamma rays emerging from the core of the Milky Way galaxy.

This view displays the entire sky at energies exceeding 1 GeV, derived from five years of data from the LAT instrument on NASA’s Fermi Gamma-ray Space Telescope. The most striking aspect is a luminous band of diffuse light along the center of the map, indicating the central plane of the Milky Way galaxy. Image credit: NASA/DOE/Fermi LAT collaboration.

Gamma rays are a form of electromagnetic radiation characterized by the shortest wavelengths and the highest energy.

The intriguing gamma-ray signal from the Milky Way’s center was initially observed in 2009 by the Large Area Telescope, the primary instrument of NASA’s Fermi Gamma-ray Space Telescope.

The source of this signal remains under discussion, with main hypotheses involving self-annihilating dark matter and undetected populations of millisecond pulsars.

“When Fermi directed its gaze toward the galaxy’s center, the outcome was unexpected,” remarked Dr. Noam Libeskind, an astrophysicist at the Leibniz Institute for Astrophysics in Potsdam.

“The telescope detected an excessive number of gamma rays, the most energetic form of light in the universe.”

“Astronomers worldwide were baffled, and numerous competing theories emerged to clarify the so-called gamma-ray excess.”

“After extensive discussion, two primary theories surfaced: either these gamma rays stem from millisecond pulsars (highly dense neutron stars rotating thousands of times per second) or from dark matter particles colliding and annihilating. Both theories, however, have their limitations.”

“Nonetheless, our findings strongly support the notion that the gamma-ray excess arises from dark matter annihilation.”

In their study, Dr. Libeskind and his team simulated the formation of the Milky Way galaxy under conditions akin to those in Earth’s neighboring universe.

They discovered that dark matter does not radiate outward from the galaxy’s core but is organized similarly to stars, suggesting that it could also contribute to the excess gamma rays.

“The Milky Way has long been recognized as existing within a spherical region filled with dark matter, often referred to as a dark matter halo,” explained Dr. Mourits Mikkel Mur, an astrophysicist at the Potsdam Leibniz Institute for Astrophysics and the University of Tartu.

“However, the degree to which this halo is aspheric or ellipsoidal remains unclear.”

“We analyzed simulations of the Milky Way and its dark matter halo and found that the flattening of this region sufficiently accounts for the gamma-ray excess due to self-annihilation of dark matter particles.”

“These calculations indicate that the search for dark matter particles capable of self-annihilation should be emphasized, bringing us closer to uncovering the enigmatic properties of these particles.”

A study of the survey results was published in this month’s edition of Physical Review Letters.

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Mikel Mur the Moor et al. 2025. Excess forms of dark matter in Fermi LAT galactic center Milky Way simulations. Physics. Pastore Rhett 135, 161005; doi: 10.1103/g9qz-h8wd

Source: www.sci.news

The disappearance of Saturn’s ring is only temporary this weekend

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Saturn’s iconic ring appears to “disappear” for several days starting this weekend, at least from a vantage point on Earth.

The ring does not actually disappear, but for a while the angle between Earth and Saturn creates something like an illusion of the universe, making it seem impossible to see the planetary ring from our perspective.

The reason this happens is related to the specific tilt of both planets. Saturn’s axis tilts 26.73 degrees from vertical to orbit the Sun. This is similar to the 23.5 degree tilt of the Earth. According to NASA. Therefore, as each planet rotates on its axis and orbits the Sun, the appearance of Saturn, including the ring, differs from what you see through a telescope or a powerful observatory on Earth.

Occasionally, Saturn’s tilt angle to Earth makes the ring accurately edge-on and appear to have no thin bands.

“They literally almost disappear,” said Sean Walker, associate editor of Sky & Telescope, a monthly magazine on science and amateur astronomy. “You can usually see the ring around Saturn, but with an edge-on view, your hair looks like a thin line of light lying around.”

A Saturn ring photographed by NASA’s Cassini spacecraft on May 15, 2017.Cassini-Huygens / NASA / JPL-Caltech / Space Science Institute

Over the last few months, Saturn’s vast rings have gradually appeared thinner when viewed through a ground-based telescope. By Sunday, the ring will reach its exact edge-on angle.

The illusion is temporary and lasts only a day or two before the ring slowly appears in vision again.

Events are relatively rare. Ring plane crossing – as the phenomenon is known – usually occurs twice during 29.4 years. This means that it can be seen from the Earth once every 13-15 years.

But unfortunately, Saturn is too close to the sun to see what Skywatcher looks like without the ring this weekend. However, another opportunity this year will be the ring will almost be edge-on on November 23rd later this year (not exactly).

Walker said he used a backyard telescope to witness the intersection of the ring plane in 1995.

“It was great,” he said. “It looked like another planet. I spent most of the night just drinking in that view.”

He said at the time he had only just begun to become interested in astronomy.

A Saturn ring photographed by NASA’s Cassini spacecraft on November 28, 2016.Cassini-Huygens / NASA / JPL-Caltech / Space Science Institute

In addition to being a quirky product of geometry, the ring plane crossing occurs due to the structure of Saturn’s ring rings. The iconic accessory consists of billions of swirling rocks and ice blocks, but is relatively flat, making it appear that the ring disappears into thin lines when tilted to the earth.

Edge-on views also make Saturn’s moon more visible, Walker said.

“When there is an intersection of these ring planes, the light that normally reflects the ring of Saturn is no longer glancing towards Earth,” he said. “That means we can detect more small moons.”

Walker said that with a regular backyard telescope, people often can find four to six months around Saturn. People may be able to detect almost 12 people during the ring plane traversing the dark sky.

“The really faint things are on the near perfect line, so it becomes clear,” he said.

After this weekend’s Ring Plain intersection, the next complete will take place in 2038. The event, according to Walker, should be visible to Earth.

“I want to see it again,” he said. “I’ll wait a little bit.”

Source: www.nbcnews.com

Existential Cosmology: Embracing the Possibility of the Universe’s Disappearance

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Billions, perhaps trillions of years from now, long after the sun has swallowed the Earth, cosmologists predict the universe will end. Some people wrestle with whether they are likely to collapse under the weight of the Big Crunch or become an infinitely empty Big Freeze that will continue to expand forever. Some believe that the end of our universe will be determined by a mysterious energy that rips the universe apart.

But there is a more immediate cataclysm that may already be heading towards us at the speed of light. They call it “big sip.”

The slurp in question begins with a quantum fluctuation, causing the bubble to roll through space like a cosmic tsunami, obliterating everything in its path. We should take this possibility seriously, says John Ellis of King's College London. In fact, the question is not so much if this apocalypse will happen, but when. “It could be happening as we speak,” he says.

Theorists like Ellis are actually surprised that such a catastrophe has not yet occurred in the observable universe. But rather than take our precarious existence for granted, they use the obvious fact that we are still here as a tool. The idea is that some weird physics is protecting us.

This kind of existential cosmology also helps physicists filter through the myriad models of the universe, and could tell us how the universe began in the first place. “Maybe you need something to stabilize it. [the universe]And it could be new physics.'' arthu rajanti…

Source: www.newscientist.com

Is the disappearance of the Y chromosome spelling the end for men?

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What might the future look like in a world without men? Recent studies indicate that the Y chromosome, a crucial factor in determining male identity, is experiencing malfunctioning.

The Y chromosome has already undergone significant degeneration and could potentially vanish entirely. But what implications would this disappearance have?

Could new sexes emerge? Or could the male species face extinction? Renowned Australian geneticist Jenny Graves, an expert on the Y chromosome, sheds light on these developments.

Why is the Y chromosome disappearing?

First, let’s revisit the concept of sex chromosomes. Women typically have two X chromosomes, while men possess one X and one Y chromosome.

These chromosome pairs, which account for about 4% of an individual’s DNA, play a vital role in determining sex.

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“Chromosomes typically occur in pairs, with men and women sharing the same sex pairs. Women have two large X chromosomes, whereas men have one X and one Y,” explains Graves.

“In comparison to the X chromosome, the Y chromosome is relatively small, containing only 45 genes, with one gene determining maleness and several others involved in sperm production. The remaining genes serve uncertain purposes. By contrast, the X chromosome contains 900-1400 genes.

Originally, the Y chromosome had over 900 genes similar to the X chromosome. Presently, only 45 genes remain. These sex chromosomes evolved from identical non-gender-associated chromosomes, rendering much of their current makeup functionally redundant.

The degeneration of the Y chromosome is not unique to humans; it also occurs in other species. For instance, fruit flies have lost the majority of their Y chromosomes.

“The loss of the Y chromosome seems to stem from a couple of factors. The Y chromosome is exclusively present in the testes, never in the ovaries; thus, it is constantly exposed to mutations during sperm production,” explains Graves.

“Sperm production involves numerous cell divisions, each susceptible to mutations that can substantially affect the chromosomes. Moreover, the Y chromosome cannot engage in genetic exchange, hindering its ability to repair mutations effectively.”

Most chromosomes repair mutations by exchanging DNA with their counterpart chromosome, a process known as recombination. However, the Y chromosome, inherited singly unlike the dual X chromosomes in women, lacks this mechanism for genetic exchange.

What does this mean for the future of the male species?

Compared to its original state, the human Y chromosome has lost 97% of ancestral genes, while the X chromosome remains relatively intact.

What are the implications of this rapid degeneration for the male species? Are we on the verge of a world devoid of human males?

“When I mention rapid degeneration, I refer to an evolutionary timeframe. Sex chromosomes have undergone roughly 180 million years of evolution in mammals. It took this long for the Y chromosome to erode to its current state,” notes Graves.

“The impending loss of the Y chromosome has stirred concern in some quarters. A rough estimate suggests it might take another six or seven million years before the chromosome completely disappears.”

Unless global billionaires achieve immortality breakthroughs, humans may never witness the initial stages of Y chromosome degradation. But hypothetically, what might this development entail?

While some species can reproduce through parthenogenesis (unfertilized egg development), humans require sperm-bearing genes for optimal functioning. These genomically imprinted genes necessitate male involvement for reproduction. However, viable alternatives exist.

“Evolving new sex-determining genes could pave the way, as seen in certain rodent species like the eastern European mole rat and Japanese spiny rat, which lack a Y chromosome entirely. These rodents adapted by relocating crucial Y chromosome genes to other chromosomes.”

Although successful in rodents, this strategy may not yield the same results in humans. While creating new sex genes is feasible, the ensuing clash between old and new genes poses uncertainties.

“This gene conflict scenario could potentially lead to divergent sex-determining systems across human populations,” Graves explains. At present, these speculations predominate. While the Y chromosome’s deterioration is evident, the future outcomes remain uncertain, encompassing the possibility of evolutionary changes resulting in new sexes.

Given the Y chromosome’s peculiarities and the substantial human population, Graves suggests that an individual born without a Y chromosome might already exist somewhere in the world, broaching intriguing evolutionary prospects.

About our expert Jenny Graves

Jenny Graves is a geneticist and professor at the La Trobe Institute for Molecular Sciences. She has authored over 430 articles and four books on genetics, establishing herself as a leading authority on human evolution and the evolving landscape of the Y chromosome.

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Source: www.sciencefocus.com

FTX: Investigating the disappearance of funds

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SAm Bankman Fried, the former CEO of bankrupt cryptocurrency exchange FTX, oversaw a dramatic collapse that led to losses of billions of dollars for customers. In a court filing, he claims that all debts owed by FTX will be fully repaid. However, the US government views his statements as disconnected from reality.

Last week, FTX administrator John Ray III, appointed to manage the bankruptcy proceedings, accused Bankman Fried of orchestrating a massive fraud and living in a state of delusion. Ray dismissed the claims made by Bankman Fried’s lawyer that no one suffered harm as “categorically, callously, and patently false.”


Banker Mann Fried faces sentencing tomorrow after being convicted of fraud and money laundering conspiracy in the collapse of his cryptocurrency exchange. His potential 100-year prison sentence contrasts with a requested six-year term from his lawyer. The US government seeks a 40 to 50-year sentence for the 32-year-old former CEO who defrauded customers of $8 billion.

The Justice Department asserts that Bankman-Fried’s attempts to downplay his crimes and seek a lighter sentence reveal a dangerous potential for future fraud. The disputed bankruptcy proceedings for FTX may continue long after his release.

FTX: New technology, old embezzlement

This crypto entrepreneur created a façade of philanthropy by using client funds for personal luxuries, influencing political figures, and promoting the pseudo-altruistic philosophy of effective altruism. Recent testimonies have labeled FTX’s collapse as traditional embezzlement.

During the trial, evidence showed that $11.3 billion meant for customers was only $2.3 billion, with the rest diverted to investments, political contributions, and real estate, with little financial record-keeping. Wray likened the situation to a severe disaster caused by Bankman Fried’s deception.

Source: www.theguardian.com