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Categories: Anthropology: General, Space: Astronomy

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X-rays of an ancient jawless fish shows earliest-known example of internal cartilage skull, unlike that of any other known vertebrate.

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A new study sheds new light on the origins of modern brain cells. Researchers find evidence that specialized secretory cells found in placozoans, tiny sea creatures the size of a grain of sand, have many similarities to the neuron, such as the genes required to create a partial synapse. From an evolutionary point of view, early neurons might have started as something like these cells, eventually gaining the ability to create a complete synapse, form axons and dendrites and create ion channels that generate fast electrical signals -- innovations which gave rise to the neuron in more complex animals such as jellyfish. Though the complete story of how the first neuron appeared remains to be told, the study demonstrates that the basic building blocks for our brain cells were forming in the ancestors of placozoans grazing inconspicuously in the shallow seas of Earth around 800 million years ago.

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Researchers discover how molecules in ancient glass rearrange and recombine with minerals over centuries to form a patina of photonic crystals -- ordered arrangements of atoms that filter and reflect light in very specific ways -- an analog of materials used in communications, lasers and solar cells.

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A team recently calculated that most of the Moon's permanently shadowed regions (PSRs) are at most around 3.4 billion years old and can contain relatively young deposits of water ice. Water resources are considered key for sustainable exploration of the Moon and beyond, but these findings suggest that current estimates for cold-trapped ices are too high.

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Scientists have used data from the James Webb Space Telescope (JWST) as part of the Cosmic Evolution Early Release Science (CEERS) Survey to change the way we think about the universe and its distant galaxies. Astronomers authored a paper confirming very bright galaxies in the early universe, while also disproving the identification of what would have been the most distant galaxy ever found.

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Herbig-Haro (HH) objects are luminous regions surrounding newborn stars, formed when stellar winds or jets of gas spewing from these newborn stars form shock waves colliding with nearby gas and dust at high speeds. This image of HH 211 from NASA's James Webb Space Telescope reveals an outflow from a Class 0 protostar, an infantile analog of our Sun when it was no more than a few tens of thousands of years old and with a mass only 8% of the present-day Sun (it will eventually grow into a star like the Sun).

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Planetary scientists have discovered that high energy electrons in Earth's plasma sheet are contributing to weathering processes on the Moon's surface and, importantly, the electrons may have aided the formation of water on the lunar surface.

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One of the most interesting and important questions in cosmology is, 'How much matter exists in the universe?' An international team has now succeeded in measuring the total amount of matter for the second time. The team determined that matter makes up 31% of the total amount of matter and energy in the universe, with the remainder consisting of dark energy.

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These new detections suggest polar ring galaxies might be more common than previously believed.

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At the center of every galaxy is a supermassive black hole. Beyond a certain size, these become active, emitting huge amounts of radiation, and are then called quasars. It is thought these are activated by the presence of massive dark matter halos (DMH) surrounding the galaxy, directing matter towards the center, feeding the black hole. A team has now surveyed hundreds of ancient quasars and found this behavior is very consistent throughout history. This is surprising, as many large-scale processes show variation throughout the life of the universe, so the mechanism of quasar activation could have implications for the evolution of the entire universe.

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As the universe evolves, scientists expect large cosmic structures to grow at a certain rate: dense regions such as galaxy clusters would grow denser, while the void of space would grow emptier.

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A new investigation with NASA's James Webb Space Telescope into K2-18 b, an exoplanet 8.6 times as massive as Earth, has revealed the presence of carbon-bearing molecules including methane and carbon dioxide. Webb's discovery adds to recent studies suggesting that K2-18 b could be a Hycean exoplanet, one which has the potential to possess a hydrogen-rich atmosphere and a water ocean-covered surface.

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A new article hints at the existence of several black holes in the Hyades cluster -- the closest open cluster to our solar system -- which would make them the closest black holes to Earth ever detected.

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Researchers investigated the relationship between historical traumatic events experienced by Alaska Native communities and epigenetic markers on genes that previous studies have linked to trauma. The new study found a similar pattern among Alaska Native participants, with specific epigenetic differences observed in those who reported experiencing the most intense symptoms of distress when reflecting on historic losses.

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Between 1840 and 1867, thousands of enslaved Africans who had been 'liberated' from slave ships intercepted by the British Royal Navy were taken to the South Atlantic island of St Helena. But little is written in history books or otherwise known about the lives of these individuals. Now, ancient DNA analyses offer the first direct evidence for the origins of St Helena's liberated Africans.

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Massive burst of X-rays detected by astronomers indicates material three times the mass of Earth burning up in a black hole. They observed a star like our own Sun being eaten away every time it orbits close. First time a Sun-like star being repeatedly disrupted by a low mass black hole has been seen, opening the possibility of a range of star and black hole combinations to be discovered.

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From the Middle Ages to the Enlightenment, 'monstrous births' -- malformed or anomalous fetuses -- were, to Western medicine, an object of superstition. In 19th-century America, they became instead an object of the 'modern scientific study of monstrosity,' a field formalized by French scientist Isidore Geoffroy Saint-Hilaire. This clinical turn was positioned against the backdrop of social, political, and economic activity that codified laws governing slavery, citizenship, immigration, family, wealth, and access to resources.

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New research has revealed the distribution of dark matter in never before seen detail, down to a scale of 30,000 light-years. The observed distribution fluctuations provide better constraints on the nature of dark matter.

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Astronomers have detected the magnetic field of a galaxy so far away that its light has taken more than 11 billion years to reach us: we see it as it was when the Universe was just 2.5 billion years old. The result provides astronomers with vital clues about how the magnetic fields of galaxies like our own Milky Way came to be.

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Researchers report that the flexible shoulders and elbows that allow us to throw a football or reach a high shelf may have evolved as a natural braking system that let our primate ancestors get out of trees without dying. The researchers used sports-analysis software to compare the climbing movements of chimpanzees and small monkeys called mangabeys. While the animals climb up trees similarly, the researchers found that the shallow, rounded shoulder joints and shortened elbow bones that chimps have -- similar to humans -- allow them to fully extend their arms above their heads when climbing down, holding onto branches like a person going down a ladder to support their greater weight. When early humans left forests for the grassy savanna, these versatile appendages would have been essential for gathering food and using tools for hunting and defense. The findings are among the first to identify the significance of 'downclimbing' in the evolution of apes and early humans.