[kylek]

The numbers on the Mars rover missions are more staggering in my opinion. From wikipedia (https://en.wikipedia.org/wiki/Mars_Exploration_Rover) :

The total cost of building, launching, landing and operating the rovers on the surface for the initial 90-sol primary mission was US$820 million.[4] Since the rovers have continued to function beyond their initial 90 sol primary mission, they have each received five mission extensions. The fifth mission extension was granted in October 2007, and ran to the end of 2009.[4][5] The total cost of the first four mission extensions was $104 million, and the fifth mission extension is expected to cost at least $20 million.[4]

Jet Propulsion Laboratory (JPL) lost contact with Spirit after last hearing from the rover on March 22, 2010 and continued attempts to regain communications lasted until May 25, 2011, bringing the elapsed mission time to 6 years 2 months 19 days, or over 25 times the original planned mission duration.[9]