We propose to investigate space weathering in carbonaceous chondrite meteorites focusing on how the 3- m spectral region, as well as the structural and chemical properties of these samples are altered…

This federal contract award to Northern Arizona University (NAU) is for a three-year study to investigate space weathering in carbonaceous chondrite meteorites. The study will focus on how the 3-micron spectral region, as well as the structural and chemical properties of these samples, are altered by ion and laser irradiation. The contract, valued at $601,926, is funded by the National Aeronautics and Space Administration (NASA) through its Solar System Workings program. This study will significantly enhance the understanding of how spectral features indicative of hydrated asteroids are altered by space weathering, which will improve the ability of scientists to use this spectral region for compositional analysis of hydrated asteroids. The contract does not have a set-aside designation, reflecting NAU's competitiveness as a research institution. NAU has a strong track record of conducting planetary science research and supporting various federal agencies through contract and grant awards.

We propose to investigate space weathering in carbonaceous chondrite meteorites focusing on how the 3- m spectral region, as well as the structural and chemical properties of these samples are altered by ION and laser irradiation. In this three-year study, we will build on our experience studying space weathering of chondritic lunar and asteroid analogs by examining weathering in relevant carbonaceous chondrite meteorites induced by laser and ION irradiation. This study will be the first to systematically investigate both space weathering processes in a suite of relevant meteorite samples, using regolith-like samples, as well as the first to study the three main processes (direct laser irradiation, direct ION irradiation, and vapor redeposition) using the same experimental setup. Using mid-infrared reflectance spectroscopy (mid-IR), x-RAY photoelectron spectroscopy (XPS), and transmission electron microscopy/ energy dispersive spectroscopy (TEM/EDS) as our main diagnostic tools, we will focus on the following overarching question: what are the characteristics of hydrated carbonaceous asteroids and meteorites that have been subjected to space weathering processes? This proposed systematic study will significantly enhance our understanding of how the spectral features indicative of hydrated asteroids are altered by space weathering. This knowledge will greatly increase the ability of scientists to use this spectral region for compositional analysis of hydrated asteroids, an approach that we anticipate will be even more common after the launch of the james webb space telescope. Additionally, while this proposal is not focused on one specific asteroid, we anticipate that our study will yield information critical for interpreting data from remote sensing observations made of osiris-REX and HAYABUSA2 missions, which are targeting what are believed to be carbonaceous asteroids. Furthermore, this work is relevant to the solar system workings program as IT seeks to understand processes that occur throughout the solar system and will consist of laboratory studies that examine physical or chemical properties and processes that may be important for the carbonaceous asteroids present in our solar system.