Meridiani Planum                                                 Mars 1°56′46′′S, 354°28′24′′E

MER landing site, Meridiani Planum, Mars

Find: 5 January 2005

Iron (IAB complex)

History: While exploring the remnants of the heat shield on Meridiani Planum, the Mars Exploration Rover (MER) Opportunity imaged the surroundings with its panoramic camera (PanCam). On sol 324, a close-by object with a maximum dimension of 31 cm across became for the first time clearly visible in one of these images. Subsequent PanCam images reveal a smooth rock surface covered by depressions partly reminiscent of regmaglypts.

Classification and Description: (Athena Science Team) Spectra obtained by the Miniature Thermal Emission spectrometer on sol 339 and 342 show a thermal emissivity of 0.35, which is only consistent with metal indicating that the object was an iron meteorite. Detailed investigations from sol 349 to 352 by the in situ instruments on the rover’s arm, the Rock Abrasion Tool (RAT), Microscopic Imager (MI), Mössbauer Spectrometer (MB), and Alpha Particle X-Ray Spectrometer (APXS), confirmed the metallic nature and allowed classification. Classification based on analyses of a brushed surface: MB, ~94% of the Fe is bound in kamacite, and APXS, dust corrected composition of iron is Ni = ~7 wt%; Ge = ~300, Ga = <70 (both ppm), consistent with its classification as an iron (IAB complex).

Specimens: Type specimen and main mass, Mars.