Tag Archives: Remarkably

A Remarkably Tight Cluster of Protostars Likely Discovered

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Artist’s rendition of a Population III star that existed 100 million years after the Big Bang

Noir Lab/NSF/AURA/J. da Silva/Space Engine/M. Zamani

We may have finally observed the first generation of stars. After decades of searching for these pristine giants, known as Population III stars, astronomers have found their most promising candidate yet.

Population III stars are anticipated to be markedly distinct from today’s stars, or Population I stars. They are believed to have formed from pure hydrogen and helium gases before supernovae and powerful stellar winds dispersed heavier elements across the universe. These stars are also predicted to be larger and hotter than modern counterparts.

That’s precisely the case, according to Eli Visbal. Researchers from the University of Toledo in Ohio made this discovery through a detailed examination of prior James Webb Space Telescope (JWST) observations of a distant galaxy known as LAP1-B. With a redshift of 6.6, this galaxy is visible approximately 800 million years after the Big Bang. Its discovery was facilitated by the magnification of its light due to gravitational lensing by nearby galaxy clusters.

“There’s likely much more to discover in the universe, but we can only see it illuminated by this expanding star cluster,” Visbal noted. When his team estimated how many Population III clusters could exist at this redshift, they figured there should be only one—exactly what they observed. “Our abundance calculations aligned perfectly with those of the previous research team,” he added.

Another advantage of LAP1-B is that it contains only enough stars to comprise several thousand times the mass of the Sun. In contrast, other Population III galaxy candidates usually have significantly larger stellar masses, which do not align with simulations of Population III cluster formation. “This is the most robust candidate we’ve encountered,” says Visbal.

Most Population III stars are thought to have existed and perished between about 100 million and 400 million years after the Big Bang, at which point there were enough heavy elements in the universe to create stars similar to those we observe today. “This object meets many criteria, but I remain somewhat skeptical because these stars emerge later in the timeline, and there may be other viable explanations,” remarks Ralph Cressen from the University of Heidelberg, Germany. “Discovering Population III clusters would be fascinating, but statistically, this would surely be an anomaly.”

However, primordial pockets of hydrogen and helium could linger longer, potentially leading to the formation of Population III stars, as Visbal suggested.

“LAP-B1 is a particularly intriguing candidate, but we are still far from the clear and undeniable indications we would need for definite identification of Population III,” comments Roberto Maiorino at Cambridge University. “[For these to truly be Population III stars] it requires an extremely fortunate combination of factors, each of which is quite rare on its own, and even rarer when they occur together. Further observations and in-depth simulations are essential to ascertain whether LAP1-B represents the first detection of these enigmatic stars.

Understanding Population III stars is crucial, as they offer insights into the formation of the universe’s first heavy elements. “They reveal how the universe’s chemistry evolved from being solely hydrogen and helium to the diverse range of chemicals, life, and entities that exist today,” Visbal states. The stars of Population III were the pioneering building blocks of the complexity encompassing us now.

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Source: www.newscientist.com

Astronomers Uncover Remarkably Rare Hierarchical Quadruple Material Systems

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A newly identified quadruple star system, referred to as UPM J1040-3551 AABBAB, comprises a pair of cold brown dwarfs along with young red dwarfs.

An artistic depiction of the UPM J1040-3551 system amidst the Milky Way, as seen by the ESA Gaia satellite. On the left, the UPM J1040-3551 AA&AB is portrayed as a distant bright orange dot, showcasing the two M-shaped stars in orbit. Conversely, in the foreground on the right, a pair of cold brown dwarfs – UPM J1040-3551 BA & BB – have been on a long trajectory from each other for decades, collectively orbiting the UPM J1040-3551 AAB in a vast orbit taking over 100,000 years to complete. Image credits: Jiaxin Zhong / Zenghua Zhang.

The UPM J1040-3551 AABBAB system is situated in the constellation Antlia, approximately 82 light-years from Earth.

In this system, AAB denotes the brighter pairs AA and AB, while BAB refers to the more distant sub-components BA and BB.

“The hierarchical structure of this system makes the findings particularly intriguing, as it is essential for maintaining stable orbits over extended periods,” explains Professor Zenghua Zhang from Nanjing University.

“These two objects have orbited individually for decades, but collectively they have circled a common center of mass for more than 100,000 years.”

The two pairs are separated by 1,656 astronomical units (Au), where 1 Au represents the average distance from the Earth to the Sun.

The brighter pair, UPM J1040-3551 AAB, appears orange when viewed in visible wavelengths.

These stars possess a temperature of 3,200 K (approximately 2,900 degrees Celsius) and have a mass about 17% that of the Sun.

With a visual magnitude of 14.6, this pair is roughly 100,000 times dimmer than Polaris, the North Star, when viewed at visible wavelengths.

The fainter pair, UPM J1040-3551 BAB, comprises two cooler brown dwarfs that emit almost no visible light and are about 1,000 times dimmer than the AAB pair in near-infrared wavelengths.

These brown dwarfs are classified as T-type, with temperatures of 820 K (550 degrees Celsius) and 690 K (420 degrees Celsius), respectively.

“This is the first documented case of a quadruple system featuring a pair of T-type brown dwarfs orbiting two stars,” states Dr. Maricruz Gálvez-Ortiz, an astronomer at the Spanish Center for Astronomy.

“This discovery presents a unique opportunity for studying these enigmatic objects.”

“Brown dwarfs, alongside a diverse array of stellar companions, are invaluable for establishing age benchmarks,” comments Hugh Jones, a professor at the University of Hertfordshire.

“The UPM J1040-3551 system is particularly significant, as H-Alpha emissions from the bright pairs suggest that the system is relatively young, estimated to be between 200 and 300 million years old.”

The research team is optimistic that high-resolution imaging techniques could eventually resolve the brown dwarf pairs, facilitating precise measurements of their orbital dynamics and masses.

“This system offers a dual benefit for brown dwarf science,” remarks Adam Burgaster, a professor at the University of California, San Diego.

“It serves as both an age benchmark for calibrating cold atmospheric models and a mass benchmark for validating evolutionary models, provided that we can effectively resolve and track these brown dwarf binaries.”

“The discovery of the UPM J1040-3551 system marks a significant milestone in enhancing our understanding of these elusive objects and the various formation pathways of stellar systems near our Solar System.”

Findings are detailed in a study published in Monthly Notices of the Royal Astronomical Society.

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Zh Zhang et al. 2025. Benchmark Brown Dwarf – I. Blue M2 + T5 Wide Binary and Possible Young People [M4 + M4] + [T7 + T8] Hierarchical rectangles. mnras 542(2): 656-668; doi: 10.1093/mnras/staf895

Source: www.sci.news

Study suggests a remarkably faraway asteroid could have been responsible for dinosaur extinction

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Research has shown that the asteroid responsible for the mass extinction that annihilated the dinosaurs 66 million years ago originated from a distant region in the solar system, unlike most asteroids that have collided with Earth.

According to European and American researchers, the dinosaur-killing asteroid formed in a cold area outside Jupiter’s orbit and contained high levels of water and carbon. Survey results The study detailing these findings was published in the journal Science on Thursday.

In their analysis of objects that have struck Earth in the last 500 million years, the researchers noted that only asteroids rich in water have caused mass extinctions like the one that wiped out the dinosaurs. Co-author François Tissot, a professor at the California Institute of Technology, explained that asteroids originating closer to the sun were significantly drier.

Tissot further stated, “All other impacts that occurred were from objects closer to the sun and just happened to hit that specific spot, so the asteroid responsible for the dinosaur extinction is truly unique in both its characteristics and origin.”

This catastrophic asteroid created the Chicxulub crater in Mexico’s Yucatan Peninsula. While direct samples of the asteroid itself were unattainable due to its fragmentation, researchers were able to analyze particles that were dispersed upon impact and settled in Earth’s strata.

The researchers specifically examined ruthenium, a rare element on Earth that can be linked back to the asteroid.

The study confirmed earlier conclusions that classified the asteroid as a carbonaceous, or C-type, asteroid, though some theories proposed it could have been a comet that caused the dinosaur extinction.

Tissot explained, “Comets originate from great distances from the sun and are primarily composed of ice and dust. While the ruthenium levels of a comet have not been measured, based on research indicating other elements, it seems highly improbable that the extinction-causing object was a comet.”

According to Tissot, this study represents progress in understanding the evolution of Earth.

“By delving into Earth’s history, we now have a comprehensive look at its evolution,” he remarked. “This allows us to pose new questions about our planet.”

Source: www.nbcnews.com

Freeze-dried jerky with remarkably well-preserved mammoth DNA.

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39,000-year-old mammoth leg

Love Darren/Stockholm University

The woolly mammoth, which died 52,000 years ago, has been so well preserved that it’s now possible to sequence its entire genome and reconstruct the three-dimensional structure of its chromosomes. This information provides unprecedented details about how the animal’s genes moved throughout its life. This incredible feat was made possible because the animal’s remains were naturally freeze-dried, preserving its DNA in a glass-like state.

Scientists discovered the remains of a mammoth preserved in permafrost in a Siberian cave in 2018. The mammoth’s tissue was dry, but “not as dry as commercial beef jerky,” the researchers said. Olga Dudchenko “It was, in fact, hairy,” says a researcher at Baylor College of Medicine in Texas. Wanting to find out what genetic information they could find, Dudchenko and his colleagues took a sample of flesh from behind the mammoth’s ear and sequenced its DNA.

“Until now, scientists have only been able to find small parts of the mammoth’s genome because DNA molecules begin to degrade when an animal dies, but to the researchers’ surprise, the animal’s chromosomes were completely preserved. “This was quite a surprise, as it doesn’t match anything we’ve analyzed so far from 52,000 years ago,” the researchers say. Juan Antonio Rodriguez Members of a research team from the University of Copenhagen in Denmark.

They also found that mammoths had 28 pairs of chromosomes, the same number as their closest living relative, the Asian elephant. The three-dimensional structure of the chromosomes was also preserved, which helps distinguish active from inactive genes. For example, the genes responsible for hair growth in mammoths were more active than in elephants, allowing the researchers to determine why they have such thick fur.

Identifying whether mammoth or elephant genes are more active could aid in so-called de-extinction efforts, he said. Hendrik Poyner “To get as close as possible to a real mammoth, [genetic] “The skeleton of a mammoth is different from that of an Asian elephant,” he says. Understanding which genes to tweak, such as the one that produces lots of hair, could help create a more realistic-looking and sounding animal that, while not a bona fide mammoth, more closely resembles the ancient pachyderm.

But how did this DNA remain intact for more than 50,000 years? The researchers attribute it to the cave’s ideal conditions, which cooled and dried the animal. “The sample lost much of its moisture during the cold, dry Siberian winter,” says Dudchenko. She adds that a similar drying process occurs during the production of foods such as prosciutto.

To test their theory, the researchers put fresh and freeze-dried beef liver through a series of rigorous tests. After three days at room temperature, the fresh beef’s DNA had fragmented; but the freeze-dried version still retained its nanometer-scale chromosome structure after a year. “At that point, we wondered, rather than time killing it, what is killing it?” Dudchenko says.

So the team tried to destroy the DNA of the mammoth jerky replica by shooting it with a shotgun, running it over with a car, and having a former professional baseball player throw a fastball at it. Each time, the dried beef liver crumbled into pieces, but its microscopic structure remained intact, preserving the DNA inside. “We found that this method worked, and that it survived,” Rodriguez says.

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Source: www.newscientist.com

Australia unearths remarkably intact fossil skull of extinct colossal bird

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Australian paleontologists Genyornis neutoni A species of giant flightless Mihirn that became extinct approximately 45,000 years ago.

This illustration is, Genyornis neutoni Waterside in a wetland or marsh-like environment. The scene itself was inspired by places that exist in southern South Australia today, such as the Coorong and the Narrindjeri region of the Lower Murray River. Genyornis neutoni If this type of environment were widespread across the country, many Genyornis The fossils were found in Lake Carabonna, more than a day’s drive north, which is now a dry salt lake. It was probably much wetter in the past. Image by Jacob C. Blokland.

Genyornis neutoni Belongs to Dromornithidae The Mihirung is a species of flightless bird from Australia that became extinct during the Oligocene and Pleistocene epochs.

Also known as Newton’s Mihirn, this species lived in Australia between 48,000 and 45,000 years ago.

The bird was over two metres tall, weighed 220-240 kilograms, had tiny wings and huge hind legs, and laid a melon-sized egg weighing around 1.5 kilograms.

The only previous known skull of this species was reported in 1913, and it was so badly damaged that very little of the original bone remained, meaning not much could be inferred about the skull.

The well-preserved new specimen was discovered in the dry, salty lake bed of Lake Carabonna, in a remote area of ​​inland South Australia.

As would be expected from such a large bird, its skull was far from ordinary, with an enormous cranium, large upper and lower jaws, and an unusual skull crown.

The upper beak in particular displays a remarkable morphology that distinguishes this bird even from its closest relatives, which are otherwise quite similar.

“Genyornis neutoni “It had a high, mobile upper jaw like a parrot, but was shaped more like a goose, with a wide mouth opening, powerful biting force and the roof of its mouth capable of crushing soft plants and fruit,” says American zoologist Dr Phoebe McInerney. Flinders University.

“Skull features also showed undeniable and complex affinities with early-diverging waterfowl lineages, the South American screamer and, more recently, the Australian magpie goose.”

” Genyornis “The mysteries within this group have been difficult to unravel, but with this new skull we begin to piece together the puzzle that shows this species is a giant goose.”

“we, Genyornis“For the first time we’ve been able to work out the face of this bird – it’s quite different to other birds but does resemble a goose,” said Dr Trevor Worthy, also from Flinders University.

skull Genyornis neutoniImage courtesy of McInerney others., doi: 10.1080/08912963.2024.2308212.

By assessing the morphology of the skull, the researchers were able to evaluate the muscles and movements of each joint, building a detailed picture of how the head functioned.

“Bone shape and bone structure are in part related to the soft tissues that interact with them, such as muscles and ligaments and their attachment sites and pathways,” said Flinders University researcher Jacob Blokland.

“By using modern birds as a comparison, we can put flesh on fossils and bring them back to life.”

Moreover, paleontologists Genyornis neutoni It has several unusual adaptations to adapt to its aquatic habitat, allowing it to protect its ears and throat from the influx of water when its head is submerged underwater.

These adaptations provide further support that the species was nothing more than a giant prehistoric goose, and may be linked to its extinction as the freshwater bodies of northern South Australia are now mainly salt lakes.

“Thanks to this skull, we Genyornis neutoni “We now have a much better understanding of these birds, which once roamed widely across the Australian outback, and the reasons for their eventual extinction,” the researchers concluded.

their paper Published in the journal Historical Biology.

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Phoebe L. McInerney othersMysterious skull shape Genyornis neutoni Stirling & Zeitz, 1896 (Aves, Dromornithidae), with implications for functional morphology, ecology and evolution in the Gallopodidae. Historical BiologyPublished online June 3, 2024; doi: 10.1080/08912963.2024.2308212

Source: www.sci.news

Discovery of a Remarkably Large Black Hole in Our Galaxy

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This artist's impression shows the orbits of both a massive stellar black hole and its companion star

ESO/L. Calzada

Astronomers have discovered Gaia-BH3, the largest stellar black hole ever discovered. It has a mass 33 times that of the Sun and is dwarfed only by supermassive black holes and black holes formed by merging with other black holes.

At about 2000 light-years away, Gaia-BH3 is also the second closest black hole to Earth ever discovered. george seabroke Researchers at University College London used the Gaia Space Telescope to discover this stellar black hole, formed from a star that has reached the end of its life.

Because light cannot escape from a black hole, most black holes are discovered by looking for the glow of hot material orbiting around them and falling. However, BH3 is in a dormant state and does not phagocytize substances. Instead, researchers made their discovery by noticing the strange movement of a star that appeared to be orbiting a part of empty space.

The star itself is also unusual, being made almost entirely of hydrogen and helium. Most stars contain at least some heavy elements, which formed in the cores of massive stars and were distributed throughout the universe by supernovae. However, the first generation of stars would have had very low amounts of heavy elements. The composition of BH3's partner star suggests that the massive star that eventually collapsed to form BH3 was also one of these primitive objects and evolved differently from the way massive stars do today. suggests that it is possible. This would explain how black holes became so huge. If it had evolved like a normal star, it would be difficult to explain its size.

The discovery of such a massive black hole was not a complete surprise. Experiments looking for gravitational waves (ripples in space-time caused by the motion of heavy objects) have found signs of them in other galaxies.

“These gravitational wave measurements should lead us to expect that such a black hole exists in our galaxy, but until now it hasn't,” Seabrook said. And this should be just the beginning, he says. “This star is very bright, so if you find a star this bright, you generally expect to find many fainter stars.”

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Source: www.newscientist.com

Pompeii in England: Remarkably Preserved Bronze Age Village Offers Glimpse into Ancient Life

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An intact ax with an intact handle was found under one of the burnt structures on the grounds of Mast Farm.

cambridge archaeological unit

The ruins of a Bronze Age settlement in eastern England have been beautifully preserved after being destroyed by fire 3000 years ago. Exploring the ruins provides an incredible snapshot of how the British lived at the time, from what people ate for breakfast to the tools they used to build their homes.

Archaeologists first discovered the ancient wooden pillars in 1999 at the Mast Farm quarry near the small town of Whittlesea. A subsequent small-scale study tried to figure out if there was anything interesting there, he said. chris wakefield at the University of York, UK. But it wasn’t until his 2015 that Wakefield and his colleagues conducted serious excavations at the site.

The research team discovered the structural remains of four large circular dwellings (usually wooden circular dwellings with conical thatched roofs) dating from 3,000 to 2,800 years ago. Tree stumps suggest that it was built on raised platforms connected by wooden walkways over a small river that flows through the area. Judging by the size of the waterway, there may have been about 10 roundhouses in the settlement, Wakefield said.

Tree-ring analysis of wood taken from the structure suggests that the settlement was destroyed a year after its construction, with the houses falling into the muddy waters below. Wakefield said the waterlogged, oxygen-depleted environment prevented the settlement from deteriorating, resulting in its unprecedented level of preservation. The charring of objects by fire also served as a protective layer against environmental decay. “Almost everything that was in these people’s homes at the time of the fire has been preserved and is still being discovered nearly 3,000 years later,” Wakefield said.

The way items fell into the mud provided clues as to the layout of each house. Stepping through the door, the kitchen area tended to be on the east side of the house, with the sleeping area to the northwest and the livestock pens to the southeast.

Chemical analysis of kitchen utensils such as pots, bowls, cups and jars suggests that the settlement’s prehistoric inhabitants probably ate porridge, cereals, honey and stews made from beef, mutton and fish. .

“This is the best evidence we have for understanding prehistoric diets and cooking methods,” he says. Rachel Pope At the University of Liverpool, UK. “This is the closest you will ever get to walking through the doorways of a 3,000-year-old roundhouse and finding out what life was like inside.”

Illustration depicting daily life at one of the mast farm structures

Judith Dobie/Historic England

A toolbox filled with axes, sickles, and razors was a staple in every household. “One of the most beautiful things one of my colleagues found was an amazing two-part axe,” Wakefield says. “What’s amazing about this particular design is that the ax head itself is inserted into an additional piece of wood that can be replaced.”

The clothes recovered at the scene had a lush, velvety feel and were made from the finest fibers produced in Europe at the time, Wakefield said. Decorative beads, which may have been used in necklaces, have also been found throughout the site, and likely came from elsewhere in Europe or the Middle East.

The settlement has been likened to the ancient Roman city of Pompeii, which was buried in ash after a volcanic eruption in 79 AD. “Archaeologists sometimes talk about Pompeii-like discoveries, moments where time stood still, and this is one of them. Burnt-out settlements offer evidence of the time just before and after the fire some 2,900 years ago. It gives us a detailed look into people’s lives in the months leading up to it.” michael parker pearson At University College London.

“Mast Farm is not a once-in-a-generation site. It is very likely that there will never be another site that tells more about Bronze Age Britain.” Richard Maggwick At Cardiff University, UK.

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  • archeology/
  • ancient humans

Source: www.newscientist.com

Study finds that butterfly and moth genomes have remained remarkably stable over 250 million years of evolution

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This stability exists despite the incredible diversity in wing patterns, sizes, and caterpillar morphology across more than 160,000 species worldwide today, according to one study. new paper It was published in the magazine natural ecology and evolution.

lissandra belargas. Image credit: Eric Silvestre.

Butterflies and moths (in order) Lepidoptera) make up 10% of all described animal species and are extremely important pollinators and herbivores in many ecosystems.

In a new study, Professor Mark Blaxter and colleagues from the Wellcome Sanger Institute set out to understand the processes driving the evolution of chromosomes in this highly diverse group.

They analyzed and compared more than 200 high-quality chromosome-level genomes of butterflies and moths.

They identified 32 ancestral chromosomal components; Merian element Thanks to the work of pioneering 17th century entomologist Maria Sibylla Merian, most butterfly and moth species have remained intact since their last common ancestor more than 250 million years ago.

With the exception of a single ancient fusion event between two chromosomes that led to the 31 chromosomes found in most species today, the chromosomes of most modern species correspond directly to these ancestral Merian elements.

Researchers discovered that not only are chromosomes incredibly stable, but the order of genes within them is also stable.

They discovered several species with small changes, mainly involving the fusion of small autosomes and sex chromosomes. This highlights the role of chromosome length as a driver of evolutionary change.

However, scientists believe that the blue butterfly (lissandra) and the group containing cabbage butterflies (Pieris) ignored these genomic structure constraints.

These groups underwent large-scale chromosomal reshuffling, including large-scale chromosome reshuffling through chromosome breakage and fission and fusion.

This study improves our understanding of the factors that lead to genetic diversity in these insects. This will guide efforts to protect and conserve specific species facing unique challenges and environmental changes related to climate change.

“The chromosomes of most butterflies and moths living today can be directly traced back to 32 ancestral Merian elements that existed 250 million years ago,” said Dr. Charlotte Wright, researcher at the Wellcome Sanger Institute. said.

“It is surprising that even though the species has diversified extensively, its chromosomes have remained surprisingly intact.”

“This calls into question the idea that stable chromosomes may limit species diversification. Indeed, this feature may be the basis for building diversity. We We hope to find clues about rare groups that have circumvented these rules.”

“Studies like this that allow us to delve into these evolutionary processes are only possible through efforts like the Darwin Tree of Life Project, which generate high-quality, publicly available genome assemblies,” Blaxter said. the professor said.

“We are stepping up these efforts with Project Psyche, where we aim to sequence all 11,000 butterfly and moth species in Europe in collaboration with collaborators across the continent.”

“As important pollinators, herbivores, and food sources in a variety of ecosystems, and as powerful indicators of ecosystem health, a deeper understanding of the biology of butterflies and moths through Project Psyche will This will be useful for future research on adaptation and speciation for biodiversity conservation.”

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CJ light other. Comparative genomics reveals the dynamics of chromosome evolution in Lepidoptera. Nat Ecole Evol, published online on February 21, 2024. doi: 10.1038/s41559-024-02329-4

Source: www.sci.news