Flash memory or computer problems oddly occurred on both Curiosity and Opportunity around feb 27. One possibiliy is that a large solar flare resulted in radiation at Mars sufficient to temporarily corrupt the memory on both rovers. Mars is currently a few weeks away from solar conjunction, so big flare could have happened on the other side of the Sun.
Opportunity has ecovered from the event and is GO for planning a re-do of observations. We hope to have the data by Tuesday morning in time to plan a drive south.