For the fifth time, NASA has decided to extend the missions of the Spirit and Opportunity Mars rovers. The latest mission extension could see them operated through 2009, provided they hold up well. The two robots landed on Mars in 2004 and were originally intended to last for 90 days. But the two little robots have proven themselves to be survivors, holding up for years beyond their intended lifespan. Despite a few minor mechanical problems, both robots continue to be mobile and provide interesting images and scientific data to researchers here on Earth.