Tag Archives: remnants

Massive Black Holes: Potential Remnants from the Early Universe Explained

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Primordial black holes likely formed shortly after the Big Bang.

Shutterstock/Mohd. Afuza

An exceptionally massive black hole from the early universe may represent a type of exotic starless black hole first theorized by Stephen Hawking.

In August, Boyuan Liu and his team from the University of Cambridge used the James Webb Space Telescope (JWST) to uncover a peculiar galaxy named Abell 2744-QSO1. This ancient galaxy, dating back 13 billion years, harbored a black hole around 50 million times the mass of our Sun but hosted extremely few stars.

“This contradicts traditional theories which dictate that stars must form prior to or simultaneously with black holes,” Liu explained. Typically, black holes are believed to evolve when massive stars exhaust their fuel and undergo gravitational collapse.

Liu and his team conducted initial simulations suggesting that QSO1 might have originated as a primordial black hole—an exotic concept introduced by Stephen Hawking and Bernard Carr in 1974. Unlike conventional black holes, primordial black holes are thought to form from density fluctuations shortly after the Big Bang.

While most primordial black holes likely evaporated by the time of the JWST’s observations, some might have persisted, evolving into larger black holes like QSO1.

Although Liu and his team’s calculations align broadly with their observations, they remain relatively simple and do not factor in the intricate interactions among primordial black holes, gas clouds, and stars.

Now, the authors have employed advanced simulations to investigate how primordial black holes grew in the universe’s infancy. They analyzed how gas dynamics influenced the formation of early primordial black holes and how interactions with newly formed and dying stars affected them.

Their predictions about the black hole’s ultimate mass and the heavy elements present in it are congruent with the findings from QSO1.

“It’s not conclusive, but it represents a compelling possibility,” Liu stated. “These observations suggest that established black hole formation theories may not fully explain the phenomenon, making the notion of a significant primordial black hole in the early universe increasingly plausible.”

Simulations indicate that primordial black holes could be a feasible origin for QSO1, according to Roberto Maiorino, a team member involved in the discovery of black holes. “The alignment of their predicted properties with those of QSO1, in terms of black hole mass, stellar mass, and chemical composition, is both intriguing and promising.”

However, standard models of primordial black holes typically predict that their maximum mass should be around a million solar masses, while Maiorino pointed out that QSO1 is 50 times larger. “Nevertheless, it’s plausible that these primordial black holes are densely concentrated, allowing them to merge and grow rapidly,” he noted.

A further challenge arises from the requirement that for a primordial black hole to initially collapse, a burst of high-energy radiation, like that from a nearby supernova, is essential; however, no potential sources have been identified near QSO1, according to Maiorino.

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Source: www.newscientist.com

New Theory Suggests Supermassive Black Holes Are Remnants of the Universe’s First Star

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In a recent study, Professor Jonathan Tan, an astrophysicist from the University of Virginia and Chalmers Institute of Technology, suggests that the population III.1 supermassive star is the precursor to the ultra-high-massive black holes observed in the early universe. The intense high-energy photons emitted by the star ionized the surrounding hydrogen gas, creating a natural intergalactic medium that extended over millions of light-years. This process led to the formation of ultra-high massive black holes that caused a flash ionization, effectively ending the “dark age” of the universe.

An artist’s impression of the star field from population III that would have been visible hundreds of millions of years post-Big Bang. Image credits: noirlab/nsf/aura/J. da silva/SpaceEngine.

These black holes, residing at the centers of most large galaxies, including our Milky Way, typically possess masses millions or even billions of times greater than that of the Sun.

Their formation has sparked considerable debate, particularly with the NASA/ESA/CSA James Webb Space Telescope uncovering numerous such black holes located far away that date back to the universe’s early days.

Professor Tan’s theory, referred to as “Pop III.1,” posits that all supermassive black holes originate from the first stars, termed debris Population III.1 stars, which grow to enormous sizes due to energy from a dark matter annihilation process. This theory aligns with many of Webb’s latest discoveries.

In his publication, Tan presents another prediction that may illuminate our understanding of the universe’s origins.

“Our model indicates that the ultra-large star progenitors of black holes ionize the surrounding hydrogen gas extremely quickly, signaling their emergence with a bright flash that permeates all space,” stated Professor Tan.

“Notably, this additional stage of ionization occurs at a significantly faster rate than seen in typical galaxies, potentially addressing recent challenges and discrepancies in cosmology.”

“This was an unexpected connection we identified during the development of the POP III.1 model, but it could have substantial significance.”

“Professor Tan has crafted a sophisticated model that elucidates the two-stage process of star formation and ionization in the early universe,” commented Professor Richard Ellis, a distinguished observational cosmologist from the University of London.

“The initial star, created from a brief, brilliant flash of light, may have since vanished. Thus, what we observed with Webb could represent a subsequent phase. The universe continues to amaze us with its surprises.”

Professor Tan’s paper is set to be published in the Astrophysics Journal Letter.

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Jonathan C. Tan. 2025. POPIII.1 Flash ionization of the early universe by supermassive stars. apjl in press; Arxiv: 2506.18490

Source: www.sci.news

Hubble Discovers Remnants of a White Dwarf Merger 130 Light Years Away

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The White Dwarf represents the compact core that forms when stars exhaust their fuel and collapse. These remnants are the ashes of Earth-sized stars, typically about half the mass of the Sun, composed of carbon-oxygen cores surrounded by layers of helium and hydrogen. Utilizing far-ultraviolet data from the NASA/ESA Hubble Space Telescope, astronomers have identified carbon in the atmosphere of the famously large white dwarf WD 0525+526. They also determined that the overall mass of hydrogen and helium in the star’s atmosphere was significantly lower than anticipated based on single-star evolution.

An illustration of a merger with a white dwarf sub-huge star (size without scale) that would have occurred in the past. Image credit: Snehalata Sahu/Warwick University.

WD 0525+526 is located approximately 130 light years away in the constellation Auriga.

With a mass exceeding that of our Sun by 20%, this white dwarf is classified as a super-genocide, and its formation process remains poorly understood.

Typically, such white dwarfs form from the collapse of massive stars. However, Hubble’s UV data indicates that WD 0525+526 has a hydrogen-rich atmosphere originating from its core.

“In optical light, WD 0525+526 appears to be a massive yet typical white dwarf,” remarked Sneharata Saff, an astronomer at the University of Warwick.

“However, the ultraviolet observations from Hubble allowed us to detect faint carbon signatures that optical telescopes could not observe.”

“The presence of a small amount of carbon in the atmosphere suggests that this massive white dwarf is likely the product of a merger between two stars.”

“We also believe that many similar merged remnants may pose as white dwarfs in a predominantly hydrogen atmosphere.”

“Only ultraviolet observations can reveal them to us.”

Typically, hydrogen and helium create dense, barrier-like layers around the white dwarf core, concealing carbon-rich elements.

In a stellar merger, the hydrogen and helium enveloping layers can burn away almost entirely as the stars combine.

The resulting single star possesses a very thin envelope that does not prevent carbon from surfacing, which is precisely what is observed in WD 0525+526.

“We found that the hydrogen and helium layers are around one billion times thinner than those typical of a white dwarf,” noted Antoine Bedard, an astronomer at Warwick University.

“We believe these layers were stripped away during the merger, allowing carbon to manifest on the surface.”

“However, this phenomenon is also unusual, as the carbon present is about 100,000 times less than that found on the surfaces of other merged remnants.”

“Coupled with the star’s elevated temperatures—nearly four times hotter than the Sun—the diminished carbon levels suggest that WD 0525+526 evolves at a much faster pace than previously observed.”

This discovery will aid in understanding the destiny of binary star systems, which are crucial for related phenomena such as supernova explosions.

Alongside the enigma, this significantly hotter star’s carbon migrates to the surface.

Other merged remnants later cool enough for convection to bring carbon to the surface; however, WD 0525+526 remains too hot for this process.

Instead, the author identified a subtle mixing process known as semiconvection, uniquely observed in this White Dwarf.

This mechanism permits small amounts of carbon to gradually ascend into the star’s hydrogen-rich atmosphere.

“Finding conclusive proof of individual white dwarf mergers is rare,” remarked Professor Boris Gensick from Warwick University.

“Yet, ultraviolet spectroscopy enables us to detect these signals early, while carbon remains invisible at optical wavelengths.”

“Because the Earth’s atmosphere filters out UV rays, such observations must be conducted from space—currently, only Hubble is capable of this.”

“As WD 0525+526 continues to evolve and cool, we anticipate more carbon will emerge at the surface over time.”

“For now, this ultraviolet illumination offers rare insights into the early aftermath of stellar mergers.

Survey results are published today in the journal Nature Astronomy.

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S. Saff et al. The remnants of Hot White Dwarfs revealed by ultraviolet detection of carbon. Nature Astronomy Published online on August 6th, 2025. doi:10.1038/s41550-025-02590-y

Source: www.sci.news

These Rocks May Be the Final Remnants of Earth’s Early Crust

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Canadian Nuvvuagittuq Green Stone Belt may contain the world’s oldest rock

Jonathan O’Neill

About four billion years ago, magma from Earth’s mantle intruded the primitive crust of a nascent planet. Over the next period, nearly all of the planet’s early crust melted back into the mantle, leaving behind a small remnant near the site of this intrusion that still exists today.

This remnant is part of the Nuvvuagittuq Greenstone Belt along Hudson Bay’s coast in Canada. Recent analyses of the rock’s radioisotope signatures have sparked debates among geologists about whether it is indeed the oldest rock on Earth or simply very ancient.

In a study published in 2008, Jonathan O’Neill from the University of Ottawa and his team posited that the surrounding rocks could be as old as 4.3 billion years, dating back to the Hadean eon—just a few hundred million years after Earth’s formation.

While there have been discoveries of older mineral grains, these ancient Hadean rocks provide critical insights into Earth’s formative years, possibly shedding light on geological enigmas like the onset of plate tectonics and early ocean compositions.

The method used for dating the rocks has drawn controversy, particularly regarding the claimed age of 4.3 billion years. Traditionally, old rocks are dated utilizing a robust mineral known as zircon, but these volcanic rocks lack zircon. “No one can date these rocks using the popular techniques,” O’Neill remarks.

Instead, researchers analyzed the isotopes of neodymium and samarium within the rock. As samarium decays, it generates different isotopes of neodymium at predictable rates, allowing the ratio of isotopes to serve as a “clock” marking the time since the rock crystallized from magma. Interestingly, two isotopes of samarium can decay at differing rates, acting as two parallel chronometers. Disagreement arose among researchers about whether the rock was genuinely Hadean, as the two clocks provided inconsistent age estimates.

“I’m not convinced that most of the early Earth research community agrees,” states Richard Walker at the University of Maryland.

Currently, O’Neill’s team is assessing the neodymium and samarium isotopes in the rock formations dating back 4.3 billion years. By definition, such intrusions are younger than the surrounding rock layers, implying that dating an intrusion yields the minimum age for the enclosing rocks.

Detailed view of the Canada Nuvvuagittuq Green Stone Belt

David Hutt/Alamy

In the findings, the two chronological indicators tell the same tale, indicating the rocks’ age to be approximately 4.16 billion years. “Both clocks yield identical results,” O’Neill states. This consistency bolsters the theory that the surrounding rocks were indeed solidified during the Hadean eon, making them potentially the only known remnants of Earth’s ancient crust.

“I believe they present the strongest argument possible,” asserts Graham Pierson from the University of Alberta, Canada.

“The simplest interpretation of this data is that these represent the oldest rocks on Earth,” says Jesse Reimink at Pennsylvania State University. Nevertheless, he cautions that this may not be the final word on the subject, stating, “When it comes to the oldest rocks and minerals, absolute certainty is hard to come by.”

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Source: www.newscientist.com

Archaeologists Discover 3,500-Year-Old Rice Remnants in Guam

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Rice served as a fundamental crop in the Austronesian region, which includes the ancestors of Taiwan and the islands of Southeast Asia. However, it was largely unknown in the Pacific Islands during their initial encounters with Europeans, with the exceptions of Guam and the Mariana Islands. A recent study conducted by scientists from Guam, China, and Australia highlights the discovery of abundant rice husks and leafy plant oils associated with red melted pottery found in the Litidian Beach Caves in Guam, dating back between 3,500 and 3,100 years ago.

Ritidian Beach Cave, Guam. Image credit: Hsiao-Chun Hung.

The presence of early rice in Pacific Island settlements is part of a broader narrative about rice as a staple in the diet of ancient Austronesian speakers, who formed the world’s most extensive language family prior to the onset of global colonial expansions.

Austronesian communities cultivated rice in Taiwan no less than 4,800 years ago, but cultivation of rice among populations in eastern Indonesia seems to have been carried over into the more remote Pacific Islands. The Austronesian ancestors migrated from Taiwan across the Asia-Pacific region approximately 4,200 years ago.

These early islanders introduced domesticated rice from Taiwan and returned to the Yangtze River Basin in mainland China, the source of these resources.

In this context, rice’s significance in the Mariana Islands in Guam and western Micronesia has garnered significant interest, as it was the sole island in the distant Pacific where rice cultivation occurred, as evidenced by historical records from the 1500s and 1600s.

“These findings provide fresh insights into ancient migration and culture,” states Dr. Hsiao-Chun Hung, an archaeologist at the Australian National University.

“To this point, archaeological records only showed traces of rare rice in the remote Pacific Ocean, dating back perhaps 1,000 to 700 years ago. The evidence we have found pushes that timeline significantly forward.”

Rice cultivation from excavations at Litidian Beach Cave in Guam. Scale bar – 10μm. Image credits: Carson et al. , doi: 10.1126/sciadv.adw3591.

Dr. Hung and her team discovered ancient rice remnants in a cave at Ritidian Beach in northern Guam.

“Rice served as a daily staple in many ancient Asian societies, yet this discovery reveals that, in the remote Pacific Ocean, it was regarded as a valuable item reserved for rituals rather than regular consumption,” Dr. Hung remarked.

“Our investigations found no signs of ancient rice paddies, irrigation systems, or harvesting tools in Guam.”

“Our findings bolster the hypothesis that the first Pacific Islanders transported rice from the Philippines over 2,300 km of open ocean.

“This indicates not just their exceptional navigation abilities but also their foresight in storing and carrying essential resources across vast distances.

“The caves at Ritidian Beach offer unique insights into the lives of early inhabitants in the region, especially given that most other cave sites in Guam were affected during World War II.”

“Despite extensive exploration of outdoor sites, evidence of early rice usage had not been uncovered until this point.”

“This discovery highlights a profound and enduring connection between our ancestral heritage and our Asian roots.”

“Rice husks were found in the oldest cultural layer of this site, dated through a range of advanced methods including radiocarbon analyses of nearby human waste deposits.

“It is likely that rice was prepared and cooked elsewhere, as the grain processing would have left different kinds of evidence.”

“The humid cave conditions were not suitable for storing raw rice in a pot.”

“Ancient residues were only located on ceramic surfaces, ruling out conventional food storage options.”

Details of these findings are documented in a study published in the journal Advances in Science.

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Mike T. Carson et al. 2025. The earliest evidence of rice cultivation in remote Oceania: ritual use by the first islanders of the Marianas 3,500 years ago. Advances in Science 11 (26); doi:10.1126/sciadv.adw3591

Source: www.sci.news

XMM-Newton discovers two supernova remnants near the Milky Way satellite galaxy’s edge

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Named SNR J0614-7251 and SNR J0624-6948, the newly discovered supernova remains are located on the outskirts of the large Magelanic Cloud, the largest milky white satellite galaxy.

In the center of the image, stars cluster into a large Magellan cloud, a bright, dark green candy floss colored haze. Scattered in the center of the image are about 50 small yellow crosses, some of which are almost overlapping as they are very close to each other. SNR J0624-6948 (orange, high image) and SNR J0614-7251 (blue, bottom image) are seen in the lower left quarter of the image. Image credits: Eckhard Slawik/ESA/Xmm-Newton/Sasaki et al. / F. Zangrandi.

“Supranovae are stellar explosions, caused by massive star core collapse, neutron stars or black holes (core collapsing supernovae), or by thermonuclear destruction of white nuclei in binary systems. Friedrich- “We are a scientist at the same time,” said Alexander-Universität Erlangen-Nürnberg and colleague Dr. Manami Sasaki.

“Supranovae are important for galaxy material cycles and the formation of next-generation stars. Shockwave produces supernova debris that heats environmental or interstellar media to ionize, sweeping and compressing the environment, and making the environment more environmentally friendly and compressing. Enrich it. With chemical elements.”

use ESA's XMM-Newton Spaceshipastronomers discovered two supernova remnants, SNR J0614-7251 and SNR J0624-6948, in the large Magellan cloud.

“The big and small Magellan clouds are the largest satellite galaxies in the Milky Way and the closest ones,” they said.

“The Magellan Cloud is also the only satellite galaxy in the Milky Way with current active star formation.”

“A large Magellan cloud at a small distance (49,600 Parsec), its morphology is almost a hassle disk, and its low foreground absorption provides a detailed laboratory ideal for the study of large samples of the remaining supernovae. Masu.”

“Proximity allows for spatially resolved spectroscopic studies of supernova debris, and precisely known distances allow for the analysis of the energetics of each supernova debris.”

“In addition, the rich data of wide-field multi-wavelength data available provides information about the environment in which these supernova debris evolves.”

XMM-Newton observed SNR J0614-7251 and SNR J0624-6948 with three different types of X-ray light.

They show the most common chemical elements in various parts of the debris.

The center of SNR J0614-7251 is primarily made up of iron, according to the team.

This clue allowed researchers to classify this remnant for the first time as a result of a type IA supernova.

“The discovery of supernova remnants on the outskirts of the large Magellan cloud confirms that stellar explosions occur outside the galaxy and allows us to study their shocks, stellar ejectors and environment,” they said. I said that.

“It will help us to better understand the evolution of the Magellan cloud and the history of interacting galaxies and their surrounding star formation.”

“We hope that new multi-wavelength investigations will reveal more supernova remnants around the Magellan cloud.”

“This new supernova remnants allows us to study the supernova explosions and the rest of the supernova evolution in low density and low metallic environments, and better serve to better the effects of metallicity on star formation and star evolution. I can understand it.”

result It will be displayed in the journal Astronomy and Astrophysics.

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Manamisasaki et al. 2025. The remains of a supernova on the outskirts of the large Magellan cloud. A&A 693, L15; doi: 10.1051/0004-6361/202452178

Source: www.sci.news