Late fluid flow in a primitive asteroid revealed by Lu–Hf isotopes in Ryugu
Joint press release (in Japanese) by The University of Tokyo, Japan Agency for Marine-Earth Science and Technology(JAMSTEC), National Institutes for Quantum Science and Technology(QST), Institute of SCIENCE TOKYO, National Institute of Polar Research(NiPR) and Hokkaido University
Abstract
Carbonaceous asteroids are the source of the most primitive meteorites and represent leftover planetesimals that formed from ice and dust in the outer Solar System and may have delivered volatiles to the terrestrial planets. Understanding the aqueous activity of asteroids is key to deciphering their thermal, chemical and orbital evolution, with implications for the origin of water on the terrestrial planets. Analyses of the objects, in particular pristine samples returned from asteroid Ryugu, have provided detailed information on fluid–rock interactions within a few million years after parent-body formation. However, the long-term fate of asteroidal water remains poorly understood. Here we present evidence for fluid flow in a carbonaceous asteroid more than 1 billion years after formation, based on the 176Lu–176Hf decay systematics of Ryugu samples, which reflect late lutetium mobilization. Such late fluid flow was probably triggered by……
Article Information:
Iizuka, T., Shibuya, T., Hayakawa, T. et al. Late fluid flow in a primitive asteroid revealed by Lu–Hf isotopes in Ryugu. Nature (2025).
DOI：10.1038/s41586-025-09483-0
URL：https://www.nature.com/articles/s41586-025-09483-0
