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Categories: Anthropology: General, Space: Astronomy
Published How 1,000 undergraduates helped solve an enduring mystery about the sun
(via sciencedaily.com) Original source For three years at the height of the COVID-19 pandemic, a group of students spent an estimated 56,000 hours analyzing the behavior of hundreds of solar flares. Their results could help astrophysicists understand how the sun's corona reaches temperatures of millions of degrees Fahrenheit.
Published Evidence of Ice Age human migrations from China to the Americas and Japan
(via sciencedaily.com) Original source Scientists have used mitochondrial DNA to trace a female lineage from northern coastal China to the Americas. By integrating contemporary and ancient mitochondrial DNA, the team found evidence of at least two migrations: one during the last ice age, and one during the subsequent melting period. Around the same time as the second migration, another branch of the same lineage migrated to Japan, which could explain Paleolithic archeological similarities between the Americas, China, and Japan.
Published Galactic bubbles are more complex than imagined
(via sciencedaily.com) Original source Astronomers have revealed new evidence about the properties of the giant bubbles of high-energy gas that extend far above and below the Milky Way galaxy's center.
Published Webb looks for Fomalhaut's asteroid belt and finds much more
(via sciencedaily.com) Original source Astronomers used NASA's James Webb Space Telescope to image the warm dust around a nearby young star, Fomalhaut, in order to study the first asteroid belt ever seen outside of our solar system in infrared light. But to their surprise, the dusty structures are much more complex than the asteroid and Kuiper dust belts of our solar system. Overall, there are three nested belts extending out to 14 billion miles (23 billion kilometers) from the star; that's 150 times the distance of Earth from the Sun. The scale of the outermost belt is roughly twice the scale of our solar system's Kuiper Belt of small bodies and cold dust beyond Neptune. The inner belts -- which had never been seen before -- were revealed by Webb for the first time.
Published Nose shape gene inherited from Neanderthals
(via sciencedaily.com) Original source Humans inherited genetic material from Neanderthals that affects the shape of our noses, finds a new study.
Published Archaeologists map hidden NT landscape where first Australians lived more than 60,000 years ago
(via sciencedaily.com) Original source Scientists have used sub-surface imaging and aerial surveys to see through floodplains in the Red Lily Lagoon area of West Arnhem Land in Australia. These ground-breaking methods showed how this important landscape in the Northern Territory was altered as sea levels rose about 8,000 years ago.
Published Hubble follows shadow play around planet-forming disk
(via sciencedaily.com) Original source The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. In 2017, astronomers reported discovering a shadow sweeping across the face of a vast pancake-shaped gas-and-dust disk surrounding the red dwarf star. The shadow isn't from a planet, but from an inner disk slightly inclined relative to the much larger outer disk -- causing it to cast a shadow. One explanation is that an unseen planet's gravity is pulling dust and gas into the planet's inclined orbit. The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. Now, a second shadow -- playing a game of peek-a-boo -- has emerged in just a few years between observations stored in Hubble's MAST archive. This could be from yet another disk nestled inside the system. The two disks are likely evidence of a pair of planets under construction.
Published Research reveals longstanding cultural continuity at oldest occupied site in West Africa
(via sciencedaily.com) Original source Stone tools recovered from near the Senegalese coast extend occupation of the region back to 150 thousand years ago and are comparable to those seen across Africa at this time, but uniquely persist in the region until 10 thousand years ago.
Published Astronomers spot a star swallowing a planet
(via sciencedaily.com) Original source Scientists have observed a star swallowing a planet for the first time. Earth will meet a similar fate in 5 billion years.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.
Published Astronomers find distant gas clouds with leftovers of the first stars
(via sciencedaily.com) Original source Using ESO's Very Large Telescope (VLT), researchers have found for the first time the fingerprints left by the explosion of the first stars in the Universe. They detected three distant gas clouds whose chemical composition matches what we expect from the first stellar explosions. These findings bring us one step closer to understanding the nature of the first stars that formed after the Big Bang.
Published Scientists present evidence for a billion-years arms race between viruses and their hosts
(via sciencedaily.com) Original source Researchers have proposed a new evolutionary model for the origin of a kingdom of viruses called Bamfordvirae, suggesting a billion-years evolutionary arms race between two groups within this kingdom and their hosts.
Published Webb finds water vapor, but from a rocky planet or its star?
(via sciencedaily.com) Original source Astronomers used NASA's James Webb Space Telescope to study a rocky exoplanet known as GJ 486 b. It is too close to its star to be within the habitable zone, with a surface temperature of about 800 degrees Fahrenheit (430 degrees Celsius). And yet, their observations show hints of water vapor.
Published New research redefines mammalian tree of life
(via sciencedaily.com) Original source Scientists from around the globe are using the largest mammalian genomic dataset in history to determine the evolutionary history of the human genome in the context of mammalian evolutionary history. Their ultimate goal is to better identify the genetic basis for traits and diseases in people and other species.
Published Astronomers detect 'nearby' black hole devouring a star
(via sciencedaily.com) Original source Astronomers have discovered a new 'tidal disruption event,' in which the center of a galaxy lights up as its supermassive black hole rips apart a passing star. The outburst is the closest tidal disruption event observed to date, and one of the first to be identified at infrared wavelengths.
Published Superflare with massive, high-velocity prominence eruption
(via sciencedaily.com) Original source A team of Japanese astronomers used simultaneous ground-based and space-based observations to capture a more complete picture of a superflare on a star. The observed flare started with a very massive, high-velocity prominence eruption. These results give us a better idea of how superflares and stellar prominence eruptions occur.
Published Information 'deleted' from the human genome may be what made us human
(via sciencedaily.com) Original source What the human genome is lacking compared with the genomes of other primates might have been as crucial to the development of humankind as what has been added during our evolutionary history, according to a new study led by researchers at Yale and the Broad Institute of MIT and Harvard. The new findings, published April 28 in the journal Science, fill an important gap in what is known about historical changes to the human genome.
Published Elephant ecosystems in decline
(via sciencedaily.com) Original source Global space for Asian elephant habitats has been in rapid decline since the 1700s, a new report reveals. More than 3 million square kilometers of the Asian elephant's historic habitat range has been lost in just three centuries and may underlie present-day conflicts between elephants and people.
Published Most massive touching stars ever found will eventually collide as black holes
(via sciencedaily.com) Original source A new study looked at a known binary star (two stars orbiting around a mutual center of gravity), analyzing starlight obtained from a range of ground- and space-based telescopes. The researchers found that the stars, located in a neighboring dwarf galaxy called the Small Magellanic Cloud, are in partial contact and swapping material with each other, with one star currently 'feeding' off the other. They orbit each other every three days and are the most massive touching stars (known as contact binaries) yet observed.
Published Prolonged droughts likely spelled the end for Indus megacities
(via sciencedaily.com) Original source New research has found evidence -- locked into an ancient stalagmite from a cave in the Himalayas -- of a series of severe and lengthy droughts which may have upturned the Bronze Age Indus Civilization.