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Categories: Mathematics: Puzzles, Space: Astronomy
Published A star like a Matryoshka doll: New theory for gravastars



If gravitational condensate stars (or gravastars) actually existed, they would look similar to black holes to a distant observer. Two theoretical physicists have now found a new solution to Albert Einstein's theory of general relativity, according to which gravitational stars could be structured like a Russian matryoshka doll, with one gravastar located inside another.
Published Mysterious gap in size distribution of super-earths explained



Astronomers have uncovered evidence of how the enigmatic gap in the size distribution of exoplanets at around two Earth radii emerges. Their computer simulations demonstrate that the migration of icy, so-called sub-Neptunes into the inner regions of their planetary systems could account for this phenomenon. As they draw closer to the central star, evaporating water ice forms an atmosphere that makes the planets appear larger than in their frozen state. Simultaneously, smaller rocky planets gradually lose a portion of their original gaseous envelope, causing their measured radius to shrink over time.
Published Mimas' surprise: Tiny moon of Saturn holds young ocean beneath icy shell



Saturn's moon Mimas harbors a global ocean beneath its icy shell, discovered through analysis of its orbit by Cassini spacecraft data. This ocean formed just 5-15 million years ago, making Mimas a prime candidate for studying early ocean formation and potential for life. This discovery suggests life-essential conditions might exist on seemingly inactive moons, expanding our search for life beyond Earth.
Published A long, long time ago in a galaxy not so far away



Employing massive data sets collected through NASA's James Webb Space Telescope, astronomers are unearthing clues to conditions existing in the early universe. The team has catalogued the ages of stars in the Wolf--Lundmark--Melotte (WLM) galaxy, constructing the most detailed picture of it yet, according to the researchers. WLM, a neighbor of the Milky Way, is an active center of star formation that includes ancient stars formed 13 billion years ago.
Published Newly discovered carbon monoxide-runaway gap can help identify habitable exoplanets



A carbon monoxide (CO)-runaway gap identified in the atmospheres of Earth-like planets can help expand the search for habitable planets. This gap, identified through atmospheric modeling, is an indicator of a CO-rich atmosphere on Earth-like planets orbiting Sun-like stars. CO is an important compound for the formation of prebiotic organic compounds, which are building blocks for more complex molecules for the formation of life.
Published Which came first: Black holes or galaxies?



Black holes not only existed at the dawn of time, they birthed new stars and supercharged galaxy formation, a new analysis of James Webb Space Telescope data suggests.
Published Neptune-like exoplanets can be cloudy or clear



Astronomers have shown new atmospheric detail in a set of 15 exoplanets similar to Neptune. While none could support humanity, a better understanding of their behavior might help us to understand why we don't have a small Neptune, while most solar systems seem to feature a planet of this class.
Published Gas on the run -- ALMA spots the shadow of a molecular outflow from a quasar when the Universe was less than one billion years old



Theoretical predictions have been confirmed with the discovery of an outflow of molecular gas from a quasar when the Universe was less than a billion years old.
Published Swarming cicadas, stock traders, and the wisdom of the crowd



The springtime emergence of vast swarms of cicadas can be explained by a mathematical model of collective decision-making with similarities to models describing stock market crashes.
Published Bright galaxies put dark matter to the test



The earliest galaxies are thought to have formed as the gravitational pull of dark matter, which has been impossible to study directly, slowly drew in enough hydrogen and helium to ignite stars. But astrophysicists now show that after the Big Bang, hydrogen and helium gas bounced at supersonic speeds off dense, slowly moving clumps of cold dark matter. When the gas fell back in millennia later, stars formed all at once, creating small, exceptionally bright galaxies. If models of cold dark matter are correct, the James Webb Space Telescope should be able to find patches of bright galaxies in the early universe, potentially offering the first effective test for theories about dark matter. If it doesn't, scientists have to go back to the drawing board with dark matter.
Published The hottest catalog of the year: Comprehensive list of slow-building solar flares



Although solar flares have been classified based on the amount of energy they emit at their peak, there has not been significant study into differentiating flares since slow-building flares were first discovered in the 1980s. Scientists have now shown that there is a significant amount of slower-type flares worthy of further investigation.
Published Staggering structure in 19 nearby spiral galaxies



The James Webb Space Telescope observed 19 nearby face-on spiral galaxies in near- and mid-infrared light as part of its contributions to the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program.
Published Researchers spying for signs of life among exoplanet atmospheres



The next generation of advanced telescopes could sharpen the hunt for potential extraterrestrial life by closely scrutinizing the atmospheres of nearby exoplanets, new research suggests.
Published Astronomers spot 18 black holes gobbling up nearby stars



Scientists have identified 18 new tidal disruption events (TDEs) -- extreme instances when a nearby star is tidally drawn into a black hole and ripped to shreds. The detections more than double the number of known TDEs in the nearby universe.
Published Cosmic building blocks of life discovered through the electron microscope



Meteorites are fragments of asteroids which find their way to Earth as shooting stars and provide information on the origins of our solar system. A team of researchers has examined the so-called Winchcombe meteorite and demonstrated the existence in it of nitrogen compounds such as amino acids and heterocyclic hydrocarbons -- without applying any chemical treatment and by using a new type of detector design.
Published Astronomers unravel mysteries of planet formation and evolution in distant planetary system



TOI-1136, a dwarf star located more than 270 light years from Earth, is host to six confirmed exoplanets and a seventh as yet unconfirmed candidate. The system has provided a rich source of information on planet formation and evolution in a young solar system. Researchers used a variety of tools to compile radial velocity and transit timing variation readings to derive highly precise measurements of the exoplants' masses, orbital information and atmospheres.
Published Stars travel more slowly at Milky Way's edge



Physicists discovered stars near the edge of the Milky Way travel more slowly than those closer to its center -- a surprise suggesting our galaxy's gravitational core may have less dark matter than previously thought.
Published 'Old smokers' and 'squalling newborns' among hidden stars spotted for first time



'Hidden' stars including a new type of elderly giant nicknamed an 'old smoker' have been spotted for the first time by astronomers. The mystery objects exist at the heart of our Milky Way galaxy and can sit quietly for decades -- fading almost to invisibility -- before suddenly puffing out clouds of smoke, according to a new study.
Published Faint features in galaxy NGC 5728 revealed



A new study describes the best method to improve images obtained by the James Webb Science Telescope (JWST) using a mathematical approach called deconvolution.
Published Astrophysical jet caught in a 'speed trap'



The microquasar SS 433 stands out as one of the most intriguing objects within our Milky Way. A pair of oppositely directed beams of plasma ('jets') spirals away perpendicularly from the binary systems disk's surface at just over a quarter of the speed of light. The H.E.S.S. observatory in Namibia has now succeeded in detecting very high energy gamma rays from the jets of SS 433, and identifying the exact location within the jets of one of the galaxy's most effective particle accelerators.