Highly-satisfied NASA boffins donned their party hats on Monday to celebrate the first anniversary of their Spirit rover's martian adventure.

Spririt touched down on the Red Planet on 3 January 2004, closely folowed by Opportunity on 24 January. Although both completed their three-month primary missions back in April 2004, they have continued to do sterling service well beyond their expected lives. At present, according to the NASA press release, Spirit is "exploring the Columbia Hills within the Gusev Crater", while Opportunity is "driving toward the heat shield that protected it during descent through the martian atmosphere" so that scientists can examine the effects of atmospheric frction on the same.

NASA's Jet Propulsion Laboratory director, Dr. Charles Elachi, said: "Little did we know a year ago that we'd be celebrating a year of roving on Mars. The success of both rovers is tribute to hundreds of talented men and women who have put their knowledge and labor into this team effort."

Rover project manager, Jim Erickson, added: "The rovers are both in amazingly good shape for their age. The twins sailed through the worst of the martian winter with flying colors, and spring is coming. Both rovers are in strong positions to continue exploring, but we can't give you any guarantees." ®

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