Abundant microchondrules in 162173 Ryugu suggest a turbulent origin for primitive asteroids
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Chondrules are a characteristic feature of primitive Solar System materials and are common in all primitive meteorites except the CI-chondrites. They are thought to form owing to melting of solid dust aggregates by energetic processing within the solar nebula and thus record fundamental processes within protoplanetary disks. We report the discovery of abundant altered microchondrules (>350 ppm) with modal sizes of 6–8 µm within sample A0180 from C-type asteroid Ryugu. These microchondrules have similar log-normal size and shape distributions to normal-sized chondrules, implying evolution by similar size-sorting. We suggest here formation of microchondrules in an outer Solar System chondrule factory, located in the Jovian pressure-bump, followed by turbulent diffusion and concentration relative to chondrules by intense turbulence. Meridional flows could have also separated microchondrules from chondrules and deliver them sunwards of the pressure bump via Lindblad torque flows. Contrary to conventional wisdom we thus propose that the concentration of fine-grained, unprocessed grains could mean the most primitive asteroids did not have to form at the largest heliocentric distances.
Date Issued
2025-07-23
Date Acceptance
2025-06-17
Citation
Nature Communications, 2025, 16
ISSN
2041-1723
Publisher
Nature Portfolio
Journal / Book Title
Nature Communications
Volume
16
Copyright Statement
© The Author(s) 2025. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
License URL
Identifier
10.1038/s41467-025-61357-1
Publication Status
Published
Article Number
6466
Date Publish Online
2025-07-23