The 78-second outing took the rover only about 10 feet straight ahead but was praised by project managers at the Pasadena, Calif.-based Jet Propulsion Laboratory as a perfect test run of the craft's historic mission: to explore whether the planet was ever watery and suitable to sustain life.
"We have six wheels in the dirt. Mars is now our sandbox, and we are ready to play and learn," lab director Charles Elachi told reporters.
NASA controllers directed Spirit to make its excursion at 12:21 a.m. PST (3:21 a.m. EST), and confirmation that the rover had successfully made its first foray was confirmed with a return transmission about 90 minutes afterward.
Cheers and applause erupted from the team as images of an empty landing platform and Spirit's tracks in the Martian soil appeared on the monitor.
"That's [the] image we're waiting for. We're now on Mars," said mission official Rob Manning. "Our wheels are finally dirty. This is very exciting. Ah, what a relief!"
With Spirit on the surface, an international team of scientists will be making careful decisions about how to use the rover for examining rocks, soils and atmosphere with the array of scientific tools the craft has onboard. The rover was designed to travel dozens of yards a day.
"It's as if we get to drive a nice sports car, but in the end we're just the valets who bring it around to the front and give the keys to the science team," said JPL engineer Chris Lewicki, flight director, according to a NASA press release.
On Friday, Spirit should deploy its robotic arm and take its first photographs with its microscopic imager, said Steven Squyres of Cornell University, the mission's main scientist.
Engineers delayed the move for three days to give Spirit time to reposition itself atop its lander, where it had sat since arriving on Jan 3. The rover had to turn in place 115 degrees to line up with one of the exit ramps that ring the landing device.
Spirit's twin Mars rover, Opportunity, is scheduled to reach Mars on Jan. 24 and begin a similar examination of a site on the opposite side of the planet.