This animation shows the Mars Exploration Rover Opportunity digging a
trench near the trough dubbed "Anatolia" with its left front wheel on sol
73. It was taken by the rover's hazard-avoidance camera.
The trench was dug so that Opportunity would be able to place its
Moessbauer spectrometer on a soil target (the pile of material on the
right side of the trench) during a four-day flight software update. The
rover's alpha particle X-ray spectrometer was pointed at the sky at this
time taking calibration measurements.
Spirit performed a similar operation during its flight software
update, but its Moessbauer was placed on a rock dubbed "Route 66." Since
there are no rocks at Opportunity's current location, rover team members
chose a patch of soil.
The trench itself is 95 centimeters (38 inches) long by 16 centimeters
(6 inches) wide by 11 centimeters (4 inches) deep. It is the deepest hole
dug by either Spirit or Opportunity to date.
