1. Spectral Variability of Rocks and Soils on the Jezero Crater Floor: A Summary of Multispectral Observations From Perseverance'sMastcam‐Z Instrument
- Author
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Rice, M. S., Johnson, J. R., Million, C. C., St. Clair, M., Horgan, B. N., Vaughan, A., Núñez, J. I., Garczynski, B., Curtis, S., Kinch, K. B., Merusi, M., Hayes, A., Bell, J. F., Duflot, L., Lapo, K., Evans, A. A., Eng, A., Cloutis, E., Brown, A., and Annex, A. M.
- Abstract
NASA's Mars‐2020 Perseverance rover spent its first year in Jezero crater studying the mafic lava flows of the Máaz formation and the ultramafic cumulates of the Séítah formation, both of which have undergone minor alteration and are variably covered by coatings, dust, and/or soil deposits. Documenting the rock and soil characteristics across the crater floor is critical for establishing the geologic context of Perseverance's cached samples—which will eventually be returned to Earth—and for interpreting the deposition and modification of the Máaz and Séítah formations. Mastcam‐Z, a pair of multispectral, stereoscopic zoom‐lens cameras, provides broadband red/green/blue and narrowband visible to near‐infrared images (VNIR, 440–1,020 nm). From multispectral observations from sols 0 to 380, we compiled a database of ∼2,400 representative Mastcam‐Z spectra. We analyzed principal components, spectral parameters, and laboratory spectra of pure minerals and natural rock surfaces to interpret the spectral diversity of rocks and soils. We define eight spectral classes of rocks: Dusty, Hematite‐like, Coated, Low‐Ca Pyroxene‐like, Olivine‐like, Weathered Olivine‐like, Fe‐rich Pyroxene‐like, and Dark Oxide‐like. The variability of soil spectra in the Jezero crater floor is controlled primarily by the amount of dust and indicates a largely consistent soil mineralogy across the traverse, with the exception of the area disturbed by the landing event. In comparison to rock spectra from the Curiosity rover's Mastcam instrument in Gale crater, rocks on the Jezero crater floor are generally less spectrally diverse, but the Olivine‐like rocks within the Séítah formation represent a new spectral rock class in Mars surface exploration. NASA's Mars‐2020 Perseverance rover spent its first year in Jezero crater studying rocks that formed in lava flows. These rocks were altered slightly by small amounts of water and are covered with dust and other coatings. Understanding these rocks, and the soils across Perseverance's traverse, is important for two reasons: Perseverance has collected rock and soil samples, which will be the first samples from Mars to be sent back to Earth, and they give insights into the history of Jezero crater. Here, we describe a database of spectra that we compiled from the Mastcam‐Z instrument, which is a pair of science cameras on Perseverance's mast. We analyzed ∼2,400 spectra representing the diversity of rocks and soils across the first 380 Martian days of the mission. We find that the amount of dust in the soils controls their spectral variability. We define eight classes of rock spectra, which are controlled by varying amounts of pyroxenes, olivines, hematite, and other oxides. Compared to spectra from the Mastcam instrument, which documented the Curiosity traverse in Gale crater, the Mastcam‐Z spectra are generally less diverse. However, the Mastcam‐Z spectra of olivine‐like rocks are new, as they have not been previously encountered on Mars. We compiled a database of Mastcam‐Z spectra from the first 380 sols of Perseverance's mission in the floor of Jezero crater, MarsSoil spectral variability is controlled primarily by amounts of dust and indicates a largely consistent soil mineralogy across the traverseRock spectral variability is controlled by varying amounts of pyroxenes, olivines, hematite, and other oxides We compiled a database of Mastcam‐Z spectra from the first 380 sols of Perseverance's mission in the floor of Jezero crater, Mars Soil spectral variability is controlled primarily by amounts of dust and indicates a largely consistent soil mineralogy across the traverse Rock spectral variability is controlled by varying amounts of pyroxenes, olivines, hematite, and other oxides
- Published
- 2023
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