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Categories: Paleontology: Climate, Space: Exploration
Published NASA's Hubble hunts for intermediate-sized black hole close to home
(via sciencedaily.com) Original source Astronomers have come up with what they say is some of their best evidence yet for the presence of a rare class of 'intermediate-sized' black hole that may be lurking in the heart of the closest globular star cluster to Earth, located 6,000 light-years away.
Published Eruption of Tonga underwater volcano found to disrupt satellite signals halfway around the world
(via sciencedaily.com) Original source Researchers found that the Hunga-Tonga eruption was associated with the formation of an equatorial plasma bubble in the ionosphere, a phenomenon associated with disruption of satellite-based communications. Their findings also suggest that a long-held atmospheric model should be revised.
Published An X-ray look at the heart of powerful quasars
(via sciencedaily.com) Original source Researchers have observed the X-ray emission of the most luminous quasar seen in the last 9 billion years of cosmic history, known as SMSS J114447.77-430859.3, or J1144 for short. The new perspective sheds light on the inner workings of quasars and how they interact with their environment.
Published Ancient climate change solves mystery of vanished South African lakes
(via sciencedaily.com) Original source New evidence for the presence of ancient lakes in some of the most arid regions of South Africa suggests that Stone Age humans may have been more widespread across the continent than previously thought.
Published Half of world's largest lakes losing water
(via sciencedaily.com) Original source Fifty-three percent of the world's largest freshwater lakes are in decline, storing less water than they did three decades ago, according to a new study. The study analyzed satellite observations dating back decades to measure changes in water levels in nearly 2,000 of the world's biggest lakes and reservoirs. It found that climate change, human consumption and sedimentation are responsible.
Published Past climate change to blame for Antarctica's giant underwater landslides
(via sciencedaily.com) Original source Scientists found weak, biologically-rich layers of sediments hundreds of meters beneath the seafloor which crumbled as oceans warmed and ice sheets declined. The landslides were discovered in the eastern Ross Sea in 2017, by an international team of scientists during the Italian ODYSSEA expedition, and scientists revisited the area in 2018 as part of the International Ocean Discovery Program (IODP) Expedition 374 where they collected sediment cores to understand what caused them.
Published Radio signal reveals supernova origin
(via sciencedaily.com) Original source Astronomers reveal the origin of a thermonuclear supernova explosion. Strong emission lines of helium and the first detection of such a supernova in radio waves show that the exploding white dwarf star had a helium-rich companion.
Published NASA's Spitzer, TESS find potentially volcano-covered Earth-size world
(via sciencedaily.com) Original source Astronomers have discovered an Earth-size exoplanet, or world beyond our solar system, that may be carpeted with volcanoes. Called LP 791-18 d, the planet could undergo volcanic outbursts as often as Jupiter's moon Io, the most volcanically active body in our solar system.
Published 'Warm Ice Age' changed climate cycles
(via sciencedaily.com) Original source Approximately 700,000 years ago, a 'warm ice age' permanently changed the climate cycles on Earth. During this exceptionally warm and moist period, the polar glaciers greatly expanded. A research team identified this seemingly paradoxical connection. The shift in the Earth's climate represents a critical step in our planet's later climate development.
Published Out of this world control on Ice Age cycles
(via sciencedaily.com) Original source A research team, composed of climatologists and an astronomer, have used an improved computer model to reproduce the cycle of ice ages (glacial periods) 1.6 to 1.2 million years ago. The results show that the glacial cycle was driven primarily by astronomical forces in quite a different way than it works in the modern age. These results will help us to better understand the past, present, and future of ice sheets and the Earth's climate.
Published Astronomers observe the first radiation belt seen outside of our solar system
(via sciencedaily.com) Original source Astronomers have described the first radiation belt observed outside our solar system, using a coordinated array of 39 radio dishes from Hawaii to Germany to obtain high-resolution images. The images of persistent, intense radio emissions from an ultracool dwarf reveal the presence of a cloud of high-energy electrons trapped in the object's powerful magnetic field, forming a double-lobed structure analogous to radio images of Jupiter's radiation belts.
Published New study puts a definitive age on Saturn's rings -- they're really young
(via sciencedaily.com) Original source Physicists measured the flux of interplanetary dust around Saturn. The researchers concluded that the planet's rings formed less than 400 million years ago, making them much younger than Saturn itself.
Published Astronomers reveal the largest cosmic explosion ever seen
(via sciencedaily.com) Original source Astronomers have uncovered the largest cosmic explosion ever witnessed. The explosion is more than ten times brighter than any known supernova and three times brighter than the brightest tidal disruption event, where a star falls into a supermassive black hole.
Published Great Basin: History of water supply in one of the driest regions in the USA
(via sciencedaily.com) Original source An international team has reconstructed the evolution of groundwater in the Great Basin, USA -- one of the driest regions on Earth -- up to 350,000 years into the past with unprecedented accuracy. The results shed new light on the effects of climate change on water supply and provide important insights for the sustainable use of groundwater resources.
Published Hidden supermassive black holes brought to life by galaxies on collision course
(via sciencedaily.com) Original source Astronomers have found that supermassive black holes obscured by dust are more likely to grow and release tremendous amounts of energy when they are inside galaxies that are expected to collide with a neighbouring galaxy.
Published Celestial monsters at the origin of globular clusters
(via sciencedaily.com) Original source Globular clusters are the most massive and oldest star clusters in the Universe. They can contain up to 1 million of them. The chemical composition of these stars, born at the same time, shows anomalies that are not found in any other population of stars. Explaining this specificity is one of the great challenges of astronomy. After having imagined that supermassive stars could be at the origin, a team believes it has discovered the first chemical trace attesting to their presence in globular proto-clusters, born about 440 million years after the Big Bang.
Published Hidden views of vast stellar nurseries
(via sciencedaily.com) Original source Astronomers have created a vast infrared atlas of five nearby stellar nurseries by piecing together more than one million images. These large mosaics reveal young stars in the making, embedded in thick clouds of dust. Thanks to these observations, astronomers have a unique tool with which to decipher the complex puzzle of stellar birth.
Published Human ancestors preferred mosaic landscapes and high ecosystem diversity
(via sciencedaily.com) Original source A new study finds that early human species adapted to mosaic landscapes and diverse food resources, which would have increased our ancestor's resilience to past shifts in climate.
Published Measurement of the Universe's expansion rate weighs in on a longstanding debate in physics and astronomy
(via sciencedaily.com) Original source A team used a first-of-its-kind technique to measure the expansion rate of the Universe, providing insight that could help more accurately determine the Universe's age and help physicists and astronomers better understand the cosmos.
Published Astronomers find no young binary stars near Milky Way's black hole
(via sciencedaily.com) Original source Scientists analyzed over a decade's worth of data about 16 young supermassive stars orbiting the supermassive black hole at the center of the Milky Way galaxy. Supermassive stars typically are formed in pairs, but the new study found that all 16 of the stars were singletons. The findings support a scenario in which the supermassive black hole drives nearby stars to either merge or be disrupted, with one of the pair being ejected from the system.