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Categories: Geoscience: Volcanoes, Space: Structures and Features

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Astronomers have discovered an unusually massive black hole at the heart of one of the Milky Way's dwarf satellite galaxies, called Leo I. Almost as massive as the black hole in our own galaxy, the finding could redefine our understanding of how all galaxies -- the building blocks of the universe -- evolve.

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Mounded, luminous clouds of gas and dust glow in this Hubble image of a Herbig-Haro object known as HH 45. Herbig-Haro objects are a rarely seen type of nebula that occurs when hot gas ejected by a newborn star collides with the gas and dust around it at hundreds of miles per second, creating bright shock waves. In this image, blue indicates ionized oxygen (O II) and purple shows ionized magnesium (Mg II). Researchers were particularly interested in these elements because they can be used to identify shocks and ionization fronts. This object is located in the nebula NGC 1977, which itself is part of a complex of three nebulae called The Running Man. NGC 1977 -- like its companions NGC 1975 and NGC 1973 -- is a reflection nebula, which means that it doesn't emit light on its own, but reflects light from nearby stars, like a streetlight illuminating fog. Hubble observed this region to look for stellar jets and planet-forming disks around young stars, and examine how their environment affects the evolution of such disks.

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A team of scientists has identified an additional force that likely contributed to a mass extinction event 250 million years ago. Its analysis of minerals in southern China indicate that volcano eruptions produced a 'volcanic winter' that drastically lowered earth's temperatures -- a change that added to the environmental effects resulting from other phenomena at the time.

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They're born. They live once, erupting for a period that might last for days, years or decades. Then, they go dark and die. This narrative describes the life of a monogenetic volcano, a type of volcanic hazard that can pose important dangers despite an ephemeral existence. The landscape of the southwestern U.S. is heavily scarred by past eruptions of such volcanoes, and a new study marks a step toward understanding future risks for the region.

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It is estimated that about 5-10 volcanoes worldwide are capable of producing a super-eruption that could catastrophically affect global climate. One of these volcanoes hides below the waters of Lake Toba in Sumatra and has caused two super-eruptions in the last one million years. But when will the next one be? Will there be any warning signs? To answer these questions, an international team of geologists developed an analysis of the levels of uranium and lead in zircons -- a mineral typically found in explosive volcanic eruptions -- to determine how long it took the volcano to prepare for its super-eruptions.

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Researchers have long suspected a connection between information and the physical universe, with various paradoxes and thought experiments used to explore how or why information could be encoded in physical matter. A researcher attempts to shed light on exactly how much of this information is out there and presents a numerical estimate for the amount of encoded information in all the visible matter in the universe -- approximately 6 times 10 to the power of 80 bits of information.

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The more water is dissolved in the magma, the greater the risk that a volcano will explode. A new study now shows that this simple rule is only partially true. Paradoxically, high water content significantly reduces the risk of explosion.

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Galaxies can receive and exchange matter with their external environment thanks to the galactic winds created by stellar explosions. An international research team has now mapped a galactic wind for the first time. This unique observation helped to reveal where some of the Universe's missing matter is located and to observe the formation of a nebula around a galaxy.

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Dark energy, the mysterious force that causes the universe to accelerate, may have been responsible for unexpected results from the XENON1T experiment, deep below Italy's Apennine Mountains.

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A 900-year-old cosmic mystery surrounding the origins of a famous supernova first spotted over China in 1181AD has finally been solved, according to an international team of astronomers. New research says that a faint, fast expanding cloud (or nebula), called Pa30, surrounding one of the hottest stars in the Milky Way, known as Parker's Star, fits the profile, location and age of the historic supernova.

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Lava samples have revealed a new truth about the geological make-up of the Earth's crust and could have implications for volcanic eruption early warning systems, a new study has found.

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An enormous amount of gravity from a cluster of distant galaxies causes space to curve so much that light from them is bent and emanated our way from numerous directions. This 'gravitational lensing' effect has allowed astronomers to observe the same exploding star in three different places in the heavens. They predict that a fourth image of the same explosion will appear in the sky by 2037. The study provides a unique opportunity to explore not just the supernova itself, but the expansion of our universe.

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An international team of researchers developed the largest and most detailed simulation of the Universe to date and has made it freely available on the cloud to everyone. This simulation, named Uchuu, will help astronomers to interpret results from Big Data galaxy surveys.

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As their name suggests, ultradiffuse galaxies, or UDGs, are dwarf galaxies whose stars are spread out over a vast region, resulting in extremely low surface brightness, making them very difficult to detect. An international team of astronomers reports it has used sophisticated simulations to detect a few 'quenched' UDGs in low-density environments in the universe. A quenched galaxy is one that does not form stars.

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Scientists have studied an ancient supervolcano in Indonesia and found such volcanoes remain active and hazardous for thousands of years after a super-eruption, prompting the need for a rethink of how these potentially catastrophic events are predicted.

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Researchers have uncovered the physical and chemical effects of the impact of a protostellar jet in the interior of the Orion Nebula. The observations show evidence of compression and heating produced by the shock front, and the destruction of dust grains, which cause a dramatic increase in the gas phase abundance of the atoms of iron, nickel, and other heavy elements in the Orion Nebula.

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While moving around within the gas in the interstellar medium, cosmic rays kickstart the background protons, which causes a collective plasma wave movement akin to ripples on a lake. The big question is how cosmic rays deposit their momentum into the background plasma. Plasma astrophysicists review recent developments within the field of studying the streaming instability triggered by cosmic rays, which likely have more impacts on galactic dynamics and the star formation cycle than previously known.

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Astronomers calculate that the Oort Cloud may be home to more visiting objects than objects that belong to our solar system.

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Astronomers have succeeded in quantifying the proton and electron components of cosmic rays in a supernova remnant. At least 70% of the very-high-energy gamma rays emitted from cosmic rays are due to relativistic protons, according to the novel imaging analysis of radio, X-ray, and gamma-ray radiation. The acceleration site of protons, the main components of cosmic rays, has been a 100-year mystery in modern astrophysics.

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A region of active star formation in the constellation Ophiuchus is giving astronomers new insights into the conditions in which our own solar system was born. In particular, a new study of the Ophiuchus star-forming complex shows how our solar system may have become enriched with short-lived radioactive elements.