The Mars rover Opportunity touched down on the surface of the red planet in 2004, just three weeks after its twin, the Spirit rover. Opportunity’s mission was planned for 90 days, but here it is, eleven years later and still going strong. Randall Munroe of xkcd told the story of Spirit in a way that brought tears to our eyes. But when it comes to the story of Opportunity, the key emotion should be fear. Go to xkcd to see the ever-priceless hovertext.
Opportunity: The Unstoppable Mars Rover
