Mars Global Simulant MGS-1: A Rocknest-based open standard for basaltic martian regolith simulants

Kevin Cannon, Daniel Britt, Trent Smith, Ralph Fritsche, Daniel Batcheldor

The composition and physical properties of martian regolith are dramatically better understood compared to just a decade ago, particularly through the use of X-ray diffraction by the Curiosity rover. Because there are no samples of this material on Earth, researchers and engineers rely on terrestrial simulants to test future hardware and address fundamental science and engineering questions. Even with eventual sample return, the amount of material brought back would not be enough for bulk studies. However, many of the existing regolith simulants were designed 10 or 20 years ago based on a more rudimentary understanding of martian surface materials. Here, we describe the Mars Global Simulant (MGS-1), a new open standard designed as a high fidelity mineralogical analog to global basaltic regolith on Mars, as represented by the Rocknest windblown deposit at Gale crater. We developed prototype simulants using the MGS-1 standard and characterized them with imaging techniques, bulk chemistry, spectroscopy, and thermogravimetric analysis. We found the characteristics of the MGS-1 based simulant compare favorably to rover- and remote sensing-based observations from Mars, and offer dramatic improvements over past simulants in many areas. Modest amounts of simulant will be produced at the University of Central Florida. By publishing the mineral recipe and production methods, we anticipate that other groups can re-create the simulant and modify it as they see fit, leading to region-specific and application-specific versions based on a common standard.