Most rocks found on mars contain iron or minerals containing iron. The Mössbauer spectrometer is used to determine the abundance of iron in the rocks. Identification of iron-bearing minerals will yield information about early Martian environmental conditions.
The Mössbauer Spectrometer is also capable of examining the magnetic properties of surface materials and identifying minerals formed in hot, watery environments that could preserve fossil evidence of Martian life.
This device requires 12 hours to take one measurement.