Mars Opportunity rover. Computer artwork of the Opportunity rover leaving its lander (centre right) on Mars. This is one of two identical rovers sent to Mars in 2003. It will study the history of the Martian climate and hunt for evidence of ancient water. Soil and rocks will be analysed to study their composition and formation. It has a panoramic camera on the white pole at upper centre which will allow interesting areas to be chosen for study. It will travel up to 100 metres in each Martian day (sol; 24 hours 37 minutes). It is hoped it will operate for over 90 sols. Opportunity landed successfully on Mars on 24th January 2004.