NASA says its Curiosity rover has wrapped up a very successful first year of conducting science research on Mars -- that's 687 days Earth days, of course, the length of the Red Planet's year.

The rolling laboratory's primary goal has been accomplished, determining the reddish world once possessed conditions that could have supported life in the form of microbes, the space agency says.

The rover celebrated its one-year anniversary Tuesday -- again, a Martian year -- since touching down on the Red Planet on Aug. 6, 2012.

Soon after landing inside the Gale Crater, Curiosity rolled into an ancient dry riverbed, where analysis of soil samples showed water present on Mars in the past would have been the right type to sustain life in the form of bacteria, fungus or viruses.

"We see signs of a complex history of interaction between water and rock," said John Grotzinger, Curiosity project scientist at the California Institute of Technology in Pasadena.

"If Mars had living organisms, this would have been a good home for them," NASA's Jet Propulsion Laboratory in Pasadena, Calif., said in a release.

Curiosity has continued to do science, while sending more than 70,000 images of Mars back to Earth, and all of this while having to deal with a serious mechanical problem -- the rover's equivalent of a bum foot.

In late 2013, one of the rover's six wheels broke down, slowing what was already a deliberate pace of movement.

Ground controllers have kept the mission going by carefully selecting travel routes to Curiosity's science destinations and adjusting its waypoints to take the rover over less harsh patches of terrain.

"We are getting in some long drives using what we have learned," said Jim Erickson, Curiosity project manager at JPL. Curiosity has now driven a total of 4.9 miles over the Martian surface.

It has fired lasers into the Martian soil and drilled for rock samples to be analyzed in its internal laboratory instruments, all in the search for further evidence of signs of water that would confirm Mars as a habitable environment for life eons ago, researchers said.

Although the rover's primary mission, intended to last 23 months, will end soon, NASA scientists point out that rovers on Mars have demonstrated the ability to be active long after the end of their planned missions.

As evidence, they note the smaller rover Opportunity, still functioning and still returning science data a full 10 years since the end of its original planned mission duration of just 90 days.