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Categories: Paleontology: Fossils, Space: Structures and Features
Published Trilobites rise from the ashes to reveal ancient map



Ten newly discovered species of trilobites, hidden for 490 million years in a little-studied part of Thailand, could be the missing pieces in an intricate puzzle of ancient world geography.
Published Looking for 'LUCA' and the timing of cellular evolution



LUCA, the 'last universal common ancestor' of all living organisms, lived 4.32 to at most 4.52 billion years ago. What LUCA looked like is unknown, but it must have been a cell with among others ribosomal proteins and an ATP synthase.
Published Dwarf galaxies use 10-million-year quiet period to churn out stars



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.
Published Why the vast supergalactic plane is teeming with only one type of galaxy



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.
Published 'Teenage galaxies' are unusually hot, glowing with unexpected elements



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.
Published Investigating the contribution of gamma-ray blazar flares to neutrino flux



Gamma-ray flares from blazars can be accompanied by high-energy neutrino emission. To better understand this phenomenon, an international research team has statistically analyzed 145 bright blazars. They constructed weekly binned light curves and utilized a Bayesian algorithm, finding that their sample was dominated by blazars with low flare duty cycles and energy fractions. The study suggests that high-energy neutrinos of blazars might be produced mainly during the flare phase.
Published Like the phoenix, Australia's giant birds of prey rise again from limestone caves



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.
Published Research in Lake Superior reveals how sulfur might have cycled in Earth's ancient oceans



A scientists has sulfur on her mind. The yellow element is a vital macronutrient, and she's trying to understand how it cycles through the environment. Specifically, she's curious about the sulfur cycle in Earth's ancient ocean, some 3 billion years ago.
Published Radiocarbon dating meets Egyptology and Biblical accounts in the city of Gezer



New dates provide detailed insights into the timing of events in the ancient city of Gezer, according to a new study.
Published Birds set foot near South Pole in Early Cretaceous, Australian tracks show



The discovery of 27 avian footprints on the southern Australia coast -- dating back to the Early Cretaceous when Australia was still connected to Antarctica -- opens another window onto early avian evolution and possible migratory behavior.
Published Plants that survived dinosaur extinction pulled nitrogen from air



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.
Published An old star with ring-like structure: ALMA demonstrates highest resolution yet



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.
Published With unprecedented flares, stellar corpse shows signs of life



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.
Published James Webb Space Telescope detects water vapor, sulfur dioxide and sand clouds in the atmosphere of a nearby exoplanet



Astronomers have used recent observations made with the James Webb Space Telescope to study the atmosphere of the nearby exoplanet WASP-107b. Peering deep into the fluffy atmosphere of WASP-107b they discovered not only water vapor and sulfur dioxide, but even silicate sand clouds. These particles reside within a dynamic atmosphere that exhibits vigorous transport of material.
Published Downloading NASA's dark matter data from above the clouds



Data from a NASA mission to map dark matter around galaxy clusters has been saved by a new recovery system. The system allowed the retrieval of gigabytes of information, even after communication failed and the balloon-based telescope was damaged in the landing process.
Published 'Bouncing' comets could deliver building blocks for life to exoplanets



How did the molecular building blocks for life end up on Earth? One long-standing theory is that they could have been delivered by comets. Now, researchers have shown how comets could deposit similar building blocks to other planets in the galaxy.
Published Europe was not covered by dense forest before the arrival of modern humans



For decades, we believed that outside ice ages Europe was mostly covered by dense forest before the arrival of modern humans. Now, a new study shows that there was far more open and semi-open vegetation than conventionally expected.
Published Galactic 'lightsabers': Answering longstanding questions about jets from black holes



The one thing everyone knows about black holes is that absolutely everything nearby gets sucked into them. Almost everything, it turns out. Astrophysicists have now determined conclusively that energy close to the event horizon of black hole M87* is pushing outward, not inward. The researchers have also created a way to test the prediction that black holes lose rotational energy and to establish it's that energy that produces the incredibly powerful jets.
Published New study reveals surprising insights into feeding habits of carnivorous dinosaurs in North America



New research sheds light on the dining habits of ancient carnivorous dinosaurs from Jurassic rocks of the USA. A recent study explores the bite marks left on the ancient bones of the giant long-necked sauropod dinosaurs like Diplodocus and Brontosaurus by carnivorous theropod dinosaurs.
Published Tracking down quantum flickering of the vacuum



Absolutely empty -- that is how most of us envision the vacuum. Yet, in reality, it is filled with an energetic flickering: the quantum fluctuations. Experts are currently preparing a laser experiment intended to verify these vacuum fluctuations in a novel way, which could potentially provide clues to new laws in physics. A research team has developed a series of proposals designed to help conduct the experiment more effectively -- thus increasing the chances of success.