Bob Yirka is a research scientist at Phys.org.

Grains of dust from Asteroid Ryugu older than our solar system
(a) Backscattered electron (BSE) image of Ryugu thin section A0058-2. Every black area consists of ∼20 NanoSIMS maps measured. (b) An area in section C0002 with a less altered lithology than the surrounding Ryugu matrix ("clast 1"; BSE image). This area contains Mg-rich olivine, low-Ca pyroxenes, and spinel grains with sizes up to ∼15 μm (Kawasaki et al. 2022). Two of three O-anomalous grains identified in Ryugu, including one likely presolar silicate (g)–(h), were found in this region. (c)–(e) Secondary electron (SE) image of a Ryugu particle pressed into gold foil in which two presolar SiC grains were detected. The C-anomalous regions, indicated by the white arrows, are clearly associated with 28Si hotspots. (f) 17O-rich presolar oxide found in the Ryugu A0058-2 matrix. (g)–(h) This O-anomalous presolar grain was found in the less altered area shown in (b). The inlet in (g) shows a δ18O sigma image in which every pixel represents the number of standard deviations from the average values. The grain is probably a presolar silicate as Si is present in the EDX map, and Al was neither detected in the EDX map nor the NanoSIMS ion image, unlike the adjacent spinel (MgAl2O4), purple in color in (h). Credit: The Astrophysical Journal Letters (2022). DOI: 10.3847/2041-8213/ac83bd

Some of the dust samples retrieved by the Hayabusa-2 space probe are older than the sun. The group describes their analysis of the dust from the asteroid in their paper.

The Hayabusa-2 space probe was launched into space in the summer of 2014). Four years later, it rendezvoused with the asteroid. After circling the asteroid for two years, it descended to its surface and took a sample of its surface dust. It returned to Earth after it blasted off.

The sun circles the earth every 16 months. It is thought to be made from the debris of other asteroids. It's possible that it formed in the outer part of the solar system and has been creeping inward since, but it's also possible that it came from an asteroid.

Part of the sample of dust collected by the probe has been sent around the world to different researchers. The researchers looked at the age of the asteroid to see if it originated from stars or processes. The age of the grains can be determined by their signatures.

The researchers compared the grains in the dust sample to those found in meteorites. Some of the grains found in meteorites have been dated as far back as 7 billion years ago. The researchers found that the grains in the dust sample were the same as the ones in meteorites. The silicate is known to be very easy to destroy and must have been protected from the sun.

More information: Jens Barosch et al, Presolar Stardust in Asteroid Ryugu, The Astrophysical Journal Letters (2022). DOI: 10.3847/2041-8213/ac83bd Journal information: Astrophysical Journal Letters

There is a science network.

Citation: Grains of dust from asteroid Ryugu older than our solar system (2022, August 18) retrieved 18 August 2022 from https://phys.org/news/2022-08-grains-asteroid-ryugu-older-solar.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.