What's that Bunny on Mars? - Universe Today
When Opportunity sent back the first images from the surface of Mars, there was a strange object that puzzled amateurs and scientists alike - it looked like a bunny. After some analysis, scientists agreed that the object was probably about 4-5 cm long. Later images showed that the object had moved with the wind, ending up underneath the rover. This has led observers to believe that it's a piece of the rover's airbag that tore off and has been drifting around the crater, pushed by the wind.