Objectives: the iron mineralogy of the crust of mercury is key to understanding the crustal magnetism detected by messenger as well as the internal structure and evolution of the planet. However, many…

This federal contract award, valued at $292,628.48, was granted by the National Aeronautics and Space Administration (NASA) to the Regents of the University of Minnesota, doing business as the Office of Sponsored Projects Administration. The objective of the grant is to quantify the magnetic properties of iron minerals that could be present in the crust of Mercury, in order to better understand the planet's crustal magnetism and internal structure. The research will involve synthesizing and characterizing candidate minerals, such as iron sulfides, silicides, and metal alloys, that are thermodynamically stable and can retain remanent magnetization under Mercury's environmental conditions. This work is expected to provide constraints on the distribution of iron throughout Mercury's crust and upper mantle. The contract does not have a set-aside designation, and the University of Minnesota is acting as the prime contractor on this grant-funded research project.

Objectives: the iron mineralogy of the crust of mercury is key to understanding the crustal magnetism detected by messenger as well as the internal structure and evolution of the planet. However, many of the minerals that could be both chemically stable and magnetically relevant at mercury are poorly characterized in the magnetic literature. We propose to quantify the magnetic properties of iron minerals possible in mercury's crust and explore their implications for planetary structure and crustal records of ancient dynamo fields. Methods: we outline two efforts, subsequent to the identification of candidate minerals, to be conducted by postdoctoral researcher becky strauss with the guidance of PI joshua feinberg and CO-i catherine johnson. (1) the postdoctoral researcher will synthesize materials at the university of minnesota that have a variety of compositions, intended to meet two criteria. First, the material must be thermodynamically stable under the highly reducing oxygen fugacity conditions present at mercury. Second, the material must be capable of holding remanent magnetization on billion-year timescales despite mercury's high surface temperatures. Candidate minerals include iron sulfides, iron silicides, and iron metal alloys. (2) the postdoctoral researcher will conduct magnetic characterization experiments at the university of minnesota's institute for rock magnetism. These experiments will fill critical gaps in the existing rock magnetic literature using standard techniques to assess intrinsic magnetic properties, such as saturation magnetization and susceptibility with respect to temperature and grain size. Relevance: an improved understanding of the magnetic mineralogy in the crust of mercury would provide constraints on the distribution of iron throughout the planet's crust and uppermost mantle. Published thermal evolution models indicate that the modern crustal geotherm on mercury is