All articles tagged with #presolar grains
Presolar grains in meteorites—older than the Sun—are helping scientists test how our solar system formed. Evidence of aluminum-26 without iron-60 argues against a simple nearby supernova trigger and favors a scenario where winds from a Wolf-Rayet star delivered aluminum-26 into the nascent solar nebula; researchers are using nanoprobe analysis of meteorite grains to confirm this, though the origin story remains under debate.
Scientists have discovered a presolar grain of olivine in an ancient meteorite from Antarctica, revealing an extremely high isotopic ratio of magnesium-25, indicating it was formed in a hydrogen-burning supernova, a type of star recently discovered. This finding provides valuable insights into different stellar environments in the galaxy and the history of our Solar System. The grain was analyzed using atom probe tomography, offering unprecedented detail and shedding light on the formation of these rare presolar grains.
Samples from asteroid Ryugu contain clasts of rock with a chemical composition different from the rest of the asteroid, indicating they were acquired through a later impact. These clasts contain tiny grains of rock made from stars that died before the Sun existed, suggesting they originated in the outer reaches of the Solar System. The majority of these presolar grains came from asymptotic giant branch (AGB) stars, while one grain showed signs of a possible supernova origin. The impact that brought these grains to Ryugu or its parent body likely occurred after the loss of water, and some of the presolar grains may have originally come from a comet. This discovery provides insights into the early history of the Solar System.
Preserved presolar silicate grains have been discovered in surface samples collected from the Ryugu asteroid by the Hayabusa2 space probe. The unique fragments of rock, known as clasts, were found to have different chemical compositions compared to their surroundings and contained evidence of presolar grains. The presence of these grains suggests that they originated from another location in the solar system, possibly the Kuiper Belt, and somehow became embedded in the rubble field where Ryugu was located.
Samples of the asteroid Ryugu collected by the Hayabusa2 spacecraft contain fragments of stardust that are older than the solar system itself. These foreign fragments, which come from the outer solar system, provide valuable insights into the dynamics and history of our solar system. The clasts, or slivers of rock, found in the Ryugu samples are chemically different from the rest of the asteroid and contain higher concentrations of presolar grains. These grains, which originated from a comet in the Kuiper belt, were incorporated into Ryugu after its formation, shedding light on the unaltered ingredients that formed the solar system.