Jarosite and Hematite at Meridiani Planum from Opportunity's Mössbauer Spectrometer

• Published in: Science (American Association for the Advancement of Science) Vol. 306; no. 5702; pp. 1740 - 1745
• Main Authors: Klingelhöfer, G., Morris, R. V., Bernhardt, B., Schröder, C., Rodionov, D. S., de Souza, P. A., Yen, A., Gellert, R., Evlanov, E. N., Zubkov, B., Foh, J., Bonnes, U., Kankeleit, E., Gütlich, P., Ming, D. W., Renz, F., Wdowiak, T., Squyres, S. W., Arvidson, R. E.
• Format: Journal Article
• Language: English
• Published: 03.12.2004
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1104653

Mössbauer spectra measured by the Opportunity rover revealed four mineralogical components in Meridiani Planum at Eagle crater: jarosite- and hematite-rich outcrop, hematite-rich soil, olivine-bearing basaltic soil, and a pyroxene-bearing basaltic rock (Bounce rock). Spherules, interpreted to be concretions, are hematite-rich and dispersed throughout the outcrop. Hematitic soils both within and outside Eagle crater are dominated by spherules and their fragments. Olivine-bearing basaltic soil is present throughout the region. Bounce rock is probably an impact erratic. Because jarosite is a hydroxide sulfate mineral, its presence at Meridiani Planum is mineralogical evidence for aqueous processes on Mars, probably under acid-sulfate conditions.