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Categories: Offbeat: Space, Paleontology: Climate

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A subpolar species associated with Atlantic water expanded far into the Arctic Ocean during the Last Interglacial, analysis of microfossil content of sediment cores reveals. This implies that summers in the Arctic were ice free during this period.

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An international drilling expedition off the Norwegian coast confirms the theory that methane emissions from hydrothermal vents were responsible for global warming about 55 million years ago. The study shows that the vents were active in very shallow water depth or even above sea level, which would have allowed much larger amounts of methane to enter the atmosphere.

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A new image of the galaxy cluster known as 'El Gordo' is revealing distant and dusty objects never seen before, and providing a bounty of fresh science. The infrared image displays a variety of unusual, distorted background galaxies that were only hinted at in previous Hubble Space Telescope images.

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A chemical process used in the browning of food to give it its distinct smell and taste is probably happening deep in the oceans, where it helped create the conditions necessary for life. Known as the Maillard reaction after the French scientist who discovered it, the process converts small molecules of organic carbon into bigger molecules known as polymers. In the kitchen, it is used to create flavors and aromas out of sugars. But a research team argues that on the sea floor, the process has had a more fundamental effect, where it has helped to raise oxygen and reduce carbon dioxide levels in the atmosphere, to create the conditions for complex life forms to emerge and thrive on Earth.

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A patch of ocean in the North Atlantic is stubbornly cooling while much of the planet warms. This anomaly -- dubbed the 'cold blob' -- has been linked to changes in ocean circulation, but a new study found changes in large-scale atmospheric patterns may play an equally important role, according to an international research team.

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Earth is rapidly warming and scientists are developing a variety of approaches to reduce the effects of climate change. An astronomer has proposed a novel approach -- a solar shield to reduce the amount of sunlight hitting Earth, combined with a tethered, captured asteroid as a counterweight. Engineering studies using this approach could start now to create a workable design that could mitigate climate change within decades.

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In past ice ages, the intensity of summer insolation affected the emergence of warm and cold periods and played an important role in triggering abrupt climate changes, a study by climate researchers, geoscientists, and environmental physicists suggests. Using stalagmites in the European Alps, they were able to demonstrate that warm phases appeared primarily when the summer insolation reached maxima in the Northern Hemisphere.

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Scientists have trained a machine learning model in outer space, on board a satellite. This achievement could revolutionize the capabilities of remote-sensing satellites by enabling real-time monitoring and decision making for a range of applications.

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International team reports on a radio pulsar phase of a Galactic magnetar that emitted a fast radio burst in 2020; observations suggest unique origins for 'bursts' and 'pulses,' which adds to FRB formation theory.

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Many people know that stars appear to twinkle because our atmosphere bends starlight as it travels to Earth. But stars also have an innate 'twinkle' -- caused by rippling waves of gas on their surfaces -- that is imperceptible to current Earth-bound telescopes. In a new study, researchers developed the first 3D simulations of energy rippling from a massive star's core to its outer surface. Using these new models, the researchers determined, for the first time, how much stars should innately twinkle.

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As the next generation of giant, high-powered observatories begin to come online, a new study suggests that their instruments may offer scientists an unparalleled opportunity to discern what weather may be like on far-away exoplanets.

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Young stars are rambunctious! NASA's James Webb Space Telescope has captured the 'antics' of a pair of actively forming young stars, known as Herbig-Haro 46/47, in high-resolution near-infrared light. To find them, trace the bright pink and red diffraction spikes until you hit the center: The stars are within the orange-white splotch. They are buried deeply in a disk of gas and dust that feeds their growth as they continue to gain mass. The disk is not visible, but its shadow can be seen in the two dark, conical regions surrounding the central stars.

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The spiral galaxy NGC 1532, also known as Haley's Coronet, is caught in a lopsided tug of war with its smaller neighbor, the dwarf galaxy NGC 1531.

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Astronomers have gained new clues about how planets as massive as Jupiter could form. Researchers have detected large dusty clumps, close to a young star, that could collapse to create giant planets.

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Water is essential for life as we know it. However, scientists debate how it reached the Earth and whether the same processes could seed rocky exoplanets orbiting distant stars. New insights may come from the planetary system PDS 70, located 370 light-years away. The star hosts both an inner disk and outer disk of gas and dust, separated by a 5 billion-mile-wide (8 billion kilometer) gap, and within that gap are two known gas-giant planets.

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A large portion of Greenland was an ice-free tundra landscape -- perhaps covered by trees and roaming woolly mammoths -- in the recent geologic past (about 416,000 years ago), a new study shows. The results help overturn a previous view that much of the Greenland ice sheet persisted for most of the last two and a half million years. Instead, moderate warming, from 424,000 to 374,000 years ago, led to dramatic melting. At that time, the melting of Greenland caused at least five feet of sea level rise, despite atmospheric levels of heat-trapping carbon dioxide being far lower than today (280 vs. 420 ppm). This indicates that the ice sheet on Greenland may be more sensitive to human-caused climate change than previously understood -- and will be vulnerable to irreversible, rapid melting in coming centuries.

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A team has modeled the early impact history of Venus to explain how Earth's sister planet has maintained a youthful surface despite lacking plate tectonics. The team compared the early collision histories of the two bodies and determined that Venus likely experienced higher-speed, higher-energy impacts creating a super-heated core that promoted extended volcanism and resurfaced the planet.

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Researchers look at water in galaxies, its distribution and in particular its changes of state from ice to vapor, as important markers indicating areas of increased energy, in which black holes and stars are formed. A new study has now revealed the distribution of water within the J1135 galaxy, which is 12 billion light years away and formed when the Universe was a 'teenager', 1.8 billion years after the Big Bang . This water map, with unprecedented resolution, is the first ever to be obtained for such a remote galaxy. The map can help scientists to understand the physical processes taking place within J1135 and shed light on the dynamics, still partially unclear, surrounding the formation of stars, black holes and galaxies themselves.

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Astronomers have found the possible 'sibling' of a planet orbiting a distant star. The team has detected a cloud of debris that might be sharing this planet's orbit and which, they believe, could be the building blocks of a new planet or the remnants of one already formed. If confirmed, this discovery would be the strongest evidence yet that two exoplanets can share one orbit.

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New research has found the first evidence of a massive galaxy with no dark matter. The result is a challenge to the current standard model of cosmology.