TY - JOUR
T1 - Iron whiskers on asteroid Itokawa indicate sulfide destruction by space weathering
AU - Matsumoto, Toru
AU - Harries, Dennis
AU - Langenhorst, Falko
AU - Miyake, Akira
AU - Noguchi, Takaaki
N1 - Funding Information:
We appreciate the JAXA curation team for giving us an opportunity to study Itokawa samples and for assisting the study. We also thank Dr. Satoshi Nakao and Dr. Masahiro Sakai for supporting SEM observations in the IMS. The present study is supported by Grant-in-Aid for JSPS Fellows (18J00579) and JSPS Early Career Scientists (18K13610), and the JSPS core to core program: International Network of Planetary Sciences. F.L. thanks the Deutsche Forschungsgemeinschaft for funding the SEM/FIB and TEM facilities at the University of Jena via the Gottfried Wilhelm Leibniz prize (LA830/14-1).
Publisher Copyright:
© 2020, The Author(s).
PY - 2020/12/1
Y1 - 2020/12/1
N2 - Extraterrestrial iron sulfide is a major mineral reservoir of the cosmochemically and astrobiologically important elements iron and sulfur. Sulfur depletion on asteroids is a long-standing, yet unresolved phenomenon that is of fundamental importance for asteroid evolution and sulfur delivery to the Earth. Understanding the chemistry of such environments requires insight into the behavior of iron sulfides exposed to space. Here we show that troilite (FeS) grains recovered from the regolith of asteroid 25143 Itokawa have lost sulfur during long-term space exposure. We report the wide-spread occurrence of metallic iron whiskers as a decomposition product formed through irradiation of the sulfide by energetic ions of the solar wind. Whisker growth by ion irradiation is a novel and unexpected aspect of space weathering. It implies that sulfur loss occurs rapidly and, furthermore, that ion irradiation plays an important role in the redistribution of sulfur between solids and gas of the interstellar medium.
AB - Extraterrestrial iron sulfide is a major mineral reservoir of the cosmochemically and astrobiologically important elements iron and sulfur. Sulfur depletion on asteroids is a long-standing, yet unresolved phenomenon that is of fundamental importance for asteroid evolution and sulfur delivery to the Earth. Understanding the chemistry of such environments requires insight into the behavior of iron sulfides exposed to space. Here we show that troilite (FeS) grains recovered from the regolith of asteroid 25143 Itokawa have lost sulfur during long-term space exposure. We report the wide-spread occurrence of metallic iron whiskers as a decomposition product formed through irradiation of the sulfide by energetic ions of the solar wind. Whisker growth by ion irradiation is a novel and unexpected aspect of space weathering. It implies that sulfur loss occurs rapidly and, furthermore, that ion irradiation plays an important role in the redistribution of sulfur between solids and gas of the interstellar medium.
UR - http://www.scopus.com/inward/record.url?scp=85080981575&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85080981575&partnerID=8YFLogxK
U2 - 10.1038/s41467-020-14758-3
DO - 10.1038/s41467-020-14758-3
M3 - Article
C2 - 32111821
AN - SCOPUS:85080981575
SN - 2041-1723
VL - 11
JO - Nature communications
JF - Nature communications
IS - 1
M1 - 1117
ER -