Simulated asteroid materials based on carbonaceous chondrite mineralogies

Abstract

Abstract A set of high‐fidelity simulated asteroid materials, or simulants, was developed based on the mineralogy of carbonaceous chondrite meteorites. Three varieties of simulant were developed based on CI 1 chondrites (typified by Orgueil), CM 2 chondrites (typified by Murchison), and CR 2/3 chondrites (multiple samples). The simulants were designed to replicate the mineralogy and physical properties of the corresponding meteorites and anticipated asteroid surface materials as closely as is reasonably possible for bulk amounts. The simulants can be made in different physical forms ranging from larger cobbles to fine‐grained regolith. We analyzed simulant prototypes using scanning electron microscopy, X‐ray fluorescence, reflectance spectroscopy at ambient conditions and in vacuum, thermal emission spectroscopy in a simulated asteroid environment chamber, and combined thermogravimetry and evolved gas analysis. Most measured properties compare favorably to the reference meteorites and therefore to predicted volatile‐rich asteroid surface materials, including boulders, cobbles, and fine‐grained soils. However, there were also discrepancies, and mistakes were made in the original mineral formulations that will be updated in the future. The asteroid simulants are available to the community from the nonprofit Exolith Lab at UCF , and the mineral recipes are freely published for other groups to reproduce and modify as they see fit.