This image taken by the front hazard-identification camera onboard the Mars Exploration Rover Opportunity shows the rover's arm in its extended position.
This image taken shows the rover's rock abrasion tool, also known as "rat" (circular device in center), located on its instrument deployment device, or "arm."	This image shows the rover's Moessbauer spectrometer (circular device in center), located on its instrument deployment device, or "arm."	This image shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or "arm."	This iage  shows the rover's alpha particle X-ray spectrometer (circular device in center), located on its instrument deployment device, or "arm."
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