Dust grains older than the Sun found on asteroid Ryugu

Vue d'artiste de la sonde Hayabusa-2 lors de sa deuxième tentative de prise d'échantillons en juillet 2019, près d'un cratère artificiel formé sur l'astéroïde Ryugu en avril. © Akihiro Ikeshit, Jaxa

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[EN VIDÉO] These are all known asteroids in our Solar System See how many there are: Here are all the asteroids identified by astronomers since the first discovery in 1801. The number of discoveries has literally increased since the end of the 20th century. In 1950, Erwin Schrödinger, one of the founders of quantum mechanics, having worked both to elucidate the nature of life and the emergence of matter in a model of relativistic cosmology, explained in one of the four public lectures entitled “Science as a Constituent Element of Humanism” that “the isolated knowledge obtained by a group of specialists in a narrow field has in itself no value of any kind; it only has value in the synthesis that unites it to all other knowledge and only to the extent that it really contributes, in this synthesis, to answering the question: Who are we? “In fact, we are searching for our roots and our cosmic identity with space missions like that of the Japanese probe Hayabusa-2, which was in orbit around asteroid (162173) Ryugu from June 2018 to November of 2019. He took samples from it. they have since reached Earth and are still being analyzed Hayabusa 2 Mission Presentation For a fairly accurate French translation, click on the white rectangle at the bottom right . The English subtitles should then appear. Then click the nut to the right of the rectangle, then “Subtitles” and finally “Auto Translate”. Choose “French”. © DLR So they come from “a member of the Apollo family of asteroids, near-Earth asteroids, and even one of the potentially dangerous ones. It had been discovered in 1999, and it quickly became clear that it was part of the of type C, i.e. similar to carb chondrite meteorites onics known on Earth, its chemical composition therefore approaches that of the matter of the dust cloud where the primitive Solar System was born, without the light and volatile elements such as ice. It was therefore a favorite target for understanding the origin of the planets and the Sun, and therefore the origin of the biosphere and noosphere, so Hayabusa-2 gave us much more than close-up images of the asteroid (162173) Ryugu. Three years ago today (February 22, 2019) was Hayabusa2’s first touchdown! We remember the extremely tense operation. The sample collected at that time is being examined by our initial analysis team. We are excited about what we will find! pic.twitter.com/tvmyBnHOzk— HAYABUSA2@JAXA (@haya2e_jaxa) February 22, 2022 We can be convinced of this with the announcement made through an article by an international team of researchers led by Jens Barosch and Larry Nittler from the Carnegie Institution for Science published in The Astrophysical Journal Letters. Members of this team report that they have discovered in samples carried by Hayabusa-2 nothing less than presolar grains. A key to the Milky Way’s star cycle there, solid material that condensed into grains, not the cooling protoplanetary disk of gas and dust around the young Sun about 4,500 to 4,600 million years ago, if not even before the birth of the Sun, in the stellar atmospheres of stars that existed before it and from which they were expelled at the end of their lives to find themselves in the interstellar medium, then in the protosolar nebula at the origin of the Solar System. Remember that there is a real stellar cycle in the Milky Way that causes it to evolve chemically with increasing enrichment of the interstellar medium in heavy elements. In this medium, dense and cold molecular and dusty clouds gravitationally collapse, destabilized by the effect of a pressure, either density waves in the arms of our galaxy or by the shock wave of the explosion of a supernova. Upon collapsing, the clouds fragment giving nurseries of stars, some of which will evolve very quickly exploding into supernovae, injecting new heavy elements into the cloud where star formation takes place. The explosion of one such star, called Coatlicue, is thought to have caused the collapse of the protosolar cloud where our Sun was born. More generally, stars at the end of their lives will return the matter that formed them to the interstellar medium, but with new elements, an environment in which, for the same reasons, new stars will be born. This is what leads Jens Barosch to say that, in the case of the findings in the Ryugu samples, “different types of presolar masses come from different types of stars and stellar processes, which we can identify from their isotopic signatures. The possibility of identifying and studying these grains in the laboratory can help us understand the astrophysical phenomena that have shaped our Solar System, as well as other cosmic objects.” Cosmochemists can, in fact, with sophisticated microanalytical instruments, measure the abundance of various isotopic nuclei of an element that differ in their number of neutrons and compare them with those measured in carbonaceous chondrites that crashed into Earth. On this subject, and still in a press release from the Carnegie Institution for Science, Larry Nittler meanwhile explains that “the compositions and abundance of the large presolars we found in the Ryugu samples are similar to those we found previously in the carbonaceous chondrites. This gives us a more complete picture of the formation processes of our Solar System that can inform future models and experiments with samples from Hayabusa2, as well as other meteorites. ” In this video, Philip Heck talks about his research on presolar grains, minerals that formed before the birth of our solar system. “Science at FMNH” is a podcast and video series that explores behind-the-scenes science, collections and research at Chicago’s Field Museum. For a fairly accurate French translation, click on the white rectangle at the bottom right. The English subtitles should then appear. Then click on the nut to the right of the rectangle, then on “Subtitles” and finally on “Translate automatically”. Choose “French”. © Field Museum—SPECIAL OFFER: Subscribe to our media for 3 months and receive the Futura Wizard as a gift!*Take advantage of the offer now *Offer valid for any new 3-month subscription to the offer ” And participate in the life of Futura” on Patreon. — Are you interested in what you just read?
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