Engineers at mission control celebrate getting the first signal back from Spirit. Image: NASA/JPL

Dr. Steve Squyres, principal investigator for the science instruments on both Mars Exploration Rovers reacts to the images of Spirit leaving its lander. (Image and caption: NASA)

This pic was snapped as the rover came down to land at Gusev crater. Image: NASA/JPL

From left: Dave Lavery, program executive for Solar System Exploration at NASA Headquarters; Dr. Ed Weiler, associate administrator, Office of Space Science, NASA Headquarters; Pete Theisinger, (former) Mars Exploration Rover project manager and JPL lab director; and Dr. Charles Elachi celebrate the success of Spirit's landing and transmission of first images.(Image and caption: NASA)

The first color image from Spirit. Image: NASA/JPL/Cornell

Spirit used its two offset cameras to take its first 3-D pic of the Martian surface. Image: NASA/JPL

The Mars Exploration Rover team looks at some of Spirit's first images in 3-D. (NASA)

An early image showing streaks or tails of loose debris in the Martian soil, revealing the direction of prevailing winds. Image: NASA/JPL/Cornell

An animation shows Spirit standing up on its landing platform, ready to get rolling. Image: NASA/JPL

Spirit practices stowing and unstowing its arm. Image: NASA/JPL

Spirit takes its first overhead shot, showing the rover ready to roll down from its lander to the Martian surface. Image: NASA/JPL

It took many people to assemble, test and launch Spirit and Opportunity. Pictured here in JPL's Spacecraft Assembly Facility is just part of the team of engineers and technicians who were critical to the success of the mission. The team surrounds Spirit and Opportunity, with their predecessor, Sojourner, in the middle. (Image and caption: NASA)

Entry, descent and landing manager, Rob Manning (facing camera), hugs Richard Cook, the current Mars Exploration Rover project manager after Opportunity's successful landing at Meridiani Planum, Mars. To their right, Miguel San Martin, member of the attitude control systems team, cheers the victory. (Image and caption: NASA)