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Categories: Paleontology: Climate, Space: Exploration
Published Composition of asteroid Phaethon



Asteroid Phaethon, which is five kilometers in diameter, has been puzzling researchers for a long time. A comet-like tail is visible for a few days when the asteroid passes closest to the Sun during its orbit. However, the tails of comets are usually formed by vaporizing ice and carbon dioxide, which cannot explain this tail. The tail should be visible at Jupiter's distance from the Sun.
Published A gamma-ray pulsar milestone inspires innovative astrophysics and applications



Scientists have announced the discovery of nearly 300 gamma ray pulsars.
Published Solar activity likely to peak next year



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.
Published Deoxygenation levels similar to today's played a major role in marine extinctions during major past climate change event



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.
Published New way of searching for dark matter



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.
Published Alien haze, cooked in a lab, clears view to distant water worlds



Scientists have simulated conditions that allow hazy skies to form in water-rich exoplanets, a crucial step in determining how haziness muddles important telescope observations for the search of habitable worlds beyond the solar system.
Published Telescope Array detects second highest-energy cosmic ray ever



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.
Published NASA's Webb reveals new features in heart of Milky Way



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*.
Published Hydrogen detected in lunar samples, points to resource availability for space exploration



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.
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 '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 Deep dive on sea level rise: New modelling gives better predictions on Antarctic ice sheet melt



Using historical records from around Australia, an international team of researchers have put forward the most accurate prediction to date of past Antarctic ice sheet melt, providing a more realistic forecast of future sea level rise. The Antarctic ice sheet is the largest block of ice on earth, containing over 30 million cubic kilometers of water. Hence, its melting could have a devasting impact on future sea levels. To find out just how big that impact might be, the research team turned to the past.
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 A novel system for slip prevention of unmanned rovers



Planetary rovers, which help humanity explore other planets, can deviate from their targeted paths or get stuck due to slipping on loose soil. To combat this problem, researchers have developed a novel system for rovers to detect their slip condition from the change in the shape of their chassis. This novel technology, inspired by human muscles, can lead to advanced sensing technologies that make travel safer for unmanned vehicles.
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 Using eclipses to calculate the transparency of Saturn's rings



A student has measured the optical depth of Saturn's rings using a new method based on how much sunlight reached the Cassini spacecraft while it was in the shadow of the rings.
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.