Happy Martian New Year!
It's been 687 days since the Curiosity rover touched down on the Red Planet. That's the length of time it takes for Mars to make one orbit of the sun.
It is also the amount of time NASA allotted for the rover to complete its primary mission. But don't worry, the red rover isn't about to retire.
NASA chief scientist John Grotzinger says the primary mission is defined as the minimum amount of time the rover was expected to last on Mars.
“So in our case, the mission was defined to last one Mars year, and then the warranty wears off."
But he says, like with a new car, NASA expects its vehicle to live much longer than this so-called warranty period.
Related: KPCC's Mars timeline
"Curiosity looks great, she's healthy," Grotzinger said, but he points out the wheels are pretty banged up.
"That was unexpected. Mars always throws you curveballs."
Researcher had thought Curiosity's landing area to be largely sand. Instead, the site known as Gale Crater is home to jagged rocks. To minimize further damage to the rover's six-wheels, the Curiosity team is now carefully re-plotting the vehicle's path to avoid rocky terrain.
Below is an image of the rover's current path to Mount Sharp, a rocky peak at the center of Gale Crater. The vehicle's progress is marked in red. Despite driving for almost two years, the rover has traveled less than 5 miles.
A fortunate detour
This isn't the first time NASA has decided to reprogram Curiosity's route.
Shortly after the rover landed on Mars in August of 2012, the team opted to drive it toward an area dubbed Yellowknife Bay rather than to the base of Mount Sharp, as initially planned.
Mission manager Jennifer Trosper says on its way, the rover encountered some interesting rocks known as conglomerates that are typically found in slow moving water and stream beds.
"And so we thought, ‘Oh, this is great! We appear to be driving though an ancient stream bed!' " she said.
By December of 2012, the rover was exploring Yellowknife Bay by drilling into rocks and examining dirt. In March of the following year, researchers announced that mineral samples found there indicated the area was once covered in the type of water that could sustain life as we know it.
"I guess you would call it drinkable," Trosper said. "It wasn’t too acidic; it wasn’t too salty; it wasn’t too briny. This water looked to be fresh."
This was the evidence scientist needed to conclude Mars was once suitable for life. However, it still unknown if life ever existed on the Red Planet.
Many Martian discoveries
The discoveries at Yellowknife Bay were just the beginning for Curiosity.
Data from the rover is helping scientists piece together why the Martian atmosphere seems to have disappeared. The rover measured radiation levels on the planet's surface and even took a selfie with its extended camera.
As if all that weren't enough, the Curiosity mission also made the cover of the prestigious journal Science twice during its primary mission and was cited in dozens of peer-reviewed research papers.
"There has been an awful lot of scientific publications that have come out of this mission," said Emily Lakdawalla, senior editor at the Planetary Society and author of an upcoming book on Curiosity.
But Lakdawalla adds, these discoveries have happened slower than anticipated.
"This mission is more complex than any other mission anybody has ever tried to fly into space before," she said.
Curiosity represents the latest in a long string of successful missions to Mars, Lakdawalla said. But she stresses, this effort could be seen as either the pinnacle of Mars exploration or a new chapter, depending on how much funding future missions receive.
Currently, NASA is planning to send another rover to the Red Planet in 2020, provided that federal funding remains consistent.
As for Curiosity, researchers are currently in the process of requesting a new budget to extend the rover's mission for an additional two years.
In the meantime, the indefatigable Curiosity will continue the long trek to Mount Sharp. Once, it arrives, possibly later this year, the rover will examine rocks and sediment for clues as to why Mars went from warm and wet to cold and dry.