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Categories: Ecology: Extinction, Space: Astrophysics

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Researchers have discovered a new relationship between the Sun's magnetic field and its sunspot cycle, that can help predict when the peak in solar activity will occur. Their work indicates that the maximum intensity of solar cycle 25, the ongoing sunspot cycle, is imminent and likely to occur within a year.

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Scientists have made a surprising discovery that sheds new light on the role that oceanic deoxygenation (anoxia) played in one of the most devastating extinction events in Earth's history. Their finding has implications for current day ecosystems -- and serves as a warning that marine environments are likely more fragile than apparent. New research, published today in leading international journal Nature Geosciences, suggests that oceanic anoxia played an important role in ecosystem disruption and extinctions in marine environments during the Triassic--Jurassic mass extinction, a major extinction event that occurred around 200 million years ago.  Surprisingly however, the study shows that the global extent of euxinia (an extreme form of de-oxygenated conditions) was similar to the present day.

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Wondering whether whether Dark Matter particles actually are produced inside a jet of standard model particles, led researchers to explore a new detector signature known as semi-visible jets, which scientists never looked at before.

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In 1991, an experiment detected the highest-energy cosmic ray ever observed. Later dubbed the Oh-My-God particle, the cosmic ray’s energy shocked astrophysicists. Nothing in our galaxy had the power to produce it, and the particle had more energy than was theoretically possible for cosmic rays traveling to Earth from other galaxies. Simply put, the particle should not exist. On May 27, 2021, the Telescope Array experiment detected the second-highest extreme-energy cosmic ray. The newly dubbed Amaterasu particle deepens the mystery of the origin, propagation and particle physics of rare, ultra-high-energy cosmic rays.

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The latest image from NASA's James Webb Space Telescope shows a portion of the dense center of our galaxy in unprecedented detail, including never-before-seen features astronomers have yet to explain. The star-forming region, named Sagittarius C (Sgr C), is about 300 light-years from the Milky Way's central supermassive black hole, Sagittarius A*.

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A ground-breaking new discovery could transform the way astronomers understand some of the biggest and most common stars in the Universe.  Research by PhD student Jonathan Dodd and Professor René Oudmaijer, from the University's School of Physics and Astronomy, points to intriguing new evidence that massive Be stars -- until now mainly thought to exist in double stars -- could in fact be 'triples'.  The remarkable discovery could revolutionise our understanding of the objects -- a subset of B stars -- which are considered an important 'test bed' for developing theories on how stars evolve more generally. 

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In 2020 and 2021, California experienced fire activity unlike anything recorded in the modern record. When the smoke cleared, the amount of burned forest totaled ten times more than the annual average going back to the late 1800s. We know that wildlife in western forests evolved with changing habitat and disturbances like wildfire. Each species responds differently, some benefiting from openings, others losing critical habitat. What we don't know is how increasing fire severity at large scales is impacting their habitat and survival, because many species are not adapted to these types of 'megafires.'

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Researchers have discovered solar-wind hydrogen in lunar samples, which indicates that water on the surface of the Moon may provide a vital resource for future lunar bases and longer-range space exploration.

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If you look at massive galaxies teeming with stars, you might be forgiven in thinking they are star factories, churning out brilliant balls of gas. But actually, less evolved dwarf galaxies have bigger regions of star factories, with higher rates of star formation. Now, University of Michigan researchers have discovered the reason underlying this: These galaxies enjoy a 10-million-year delay in blowing out the gas cluttering up their environments. Star-forming regions are able to hang on to their gas and dust, allowing more stars to coalesce and evolve. In these relatively pristine dwarf galaxies, massive stars--stars about 20 to 200 times the mass of our sun--collapse into black holes instead of exploding as supernovae. But in more evolved, polluted galaxies, like our Milky Way, they are more likely to explode, thereby generating a collective superwind. Gas and dust get blasted out of the galaxy, and star formation quickly stops.   

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Our own Milky Way galaxy is part of a much larger formation, the local Supercluster structure, which contains several massive galaxy clusters and thousands of individual galaxies. Due to its pancake-like shape, which measures almost a billion light years across, it is also referred to as the Supergalactic Plane. Why is the vast supergalactic plane teeming with only one type of galaxies? This old cosmic puzzle may now have been solved.

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Using the James Webb Space Telescope, CECILIA Survey receives first data from galaxies forming two-to-three billion years after the Big Bang. By examining light from these 33 galaxies, researchers discovered their elemental composition and temperature. The ultra-deep spectrum revealed eight distinct elements: Hydrogen, helium, nitrogen, oxygen, silicon, sulfur, argon and nickel. The teenage galaxies also were extremely hot, reaching temperatures higher than 13,350 degrees Celsius.

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Wild caviar, a pricey delicacy made from sturgeon eggs, has been illegal for decades since poaching brought the fish to the brink of extinction. Today, legal, internationally tradeable caviar can only come from farmed sturgeon, and there are strict regulations in place to help protect the species. However, by conducting genetic and isotope analyses on caviar samples from Bulgaria, Romania, Serbia, and Ukraine -- nations bordering the remaining wild sturgeon populations -- a team of sturgeon experts found evidence that these regulations are actively being broken. Their results show that half of the commercial caviar products they sampled are illegal, and some don't even contain any trace of sturgeon.

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Australia's only vulture, and a fearsome extinct eagle, are among the earliest recorded birds of prey from the Pleistocene period more than 50,000 years ago -- and now researchers are bringing them to 'life' again.    Along with new scientific information, a bold new pictorial reconstruction of a newly named eagle and the only known Australian vulture will be unveiled at the World Heritage-listed Naracoorte Caves in South Australia's Limestone Coast this month.  

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Nature photographers posting to social media are helping improve biodiversity conservation mapping in South Asia, and the method could go global.

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Human trade and transport have led to the intentional and accidental introductions of non-native species outside of their natural range globally. These biological invasions can cause extinctions, cost trillions, and spread diseases. A study has investigated how many of these non-native species already exist worldwide and which species groups are particularly prone to become non-native.

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Ancient cycad lineages that survived the extinction of the dinosaurs may have done so by relying on symbiotic bacteria in their roots to fix atmospheric nitrogen. The finding came from an effort to understand ancient atmospheres, but became an insight into plant evolution instead.

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ALMA (Atacama Large Millimeter/submillimeter Array) has demonstrated the highest resolution yet with observations of an old star. The observations show that the star is surrounded by a ring-like structure of gas and that gas from the star is escaping to the surrounding space. Future observations with the newly demonstrated high resolution are expected to elucidate, not only the end of a star's life, but also the beginning, when planets are still forming.

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In the geological past, several groups of crocodiles evolved towards a morphology adapted to marine life. However, the extent of these adaptations and their evolutionary trajectories remained unknown. An exhaustive study of their morphology has now shed light on the evolutionary mechanisms at work, thanks to three-dimensional reconstructions.

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A new study presents crucial findings on the feeding preferences of herbivorous fishes and the sea urchin Diadema antillarum in Little Cayman. The study sheds new light on the dynamics of these herbivores and their impact on the resilience of Caribbean coral reefs.

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After a distant star's explosive death, an active stellar corpse was the likely source of repeated energetic flares observed over several months -- a phenomenon astronomers had never seen before, astronomers report.