Despite signs of wear and tear, the intrepid spacecraft is about to begin an exciting new chapter of its mission as it ascends a Martian mountain. Ten years ago on August 5, 2012, a jetpack landed NASA’s Curiosity rover on the Red Planet. That was the start of the SUV-sized explorer’s search for evidence that Mars had the conditions necessary to support tiny life billions of years ago. NASA’s Curiosity Mars rover set out to answer a big question when it landed on the Red Planet 10 years ago: Could Mars have supported ancient life? Scientists have discovered that the answer is yes, and are working to learn more about the planet’s past habitable environment. Credit: NASA/JPL-Caltech/ASU/MSSS/JHU-APL Over the past 10 years, Curiosity has driven nearly 18 miles (29 kilometers) and climbed 2,050 feet (625 meters) as it explores Gale Crater and the foothills of Mount Sharp within it. The Mars rover has analyzed 41 rock and soil samples, relying on a range of scientific instruments to learn what they reveal about Earth’s rocky sibling. Its success prompted a team of engineers to devise ways to minimize wear and tear and keep the rover rolling. In fact, Curiosity’s mission was recently extended for another three years, allowing it to continue among NASA’s fleet of major astrobiology missions. Stay curious with NASA and celebrate the Curiosity Mars rover’s 10th anniversary on the Red Planet with a double-sided poster listing some of the intrepid explorer’s inspiring achievements. Download it for free here. Credit: NASA/JPL-Caltech

A Bounty of Science

It’s been a busy decade for Curiosity. The roving explorer studied the Red Planet’s skies, snapping images of glowing clouds and drifting moons. The radiation sensor helps NASA figure out how to keep future astronauts safe by measuring the amount of high-energy radiation they’ll be exposed to on the surface of Mars. But more importantly, Curiosity discovered that liquid water, as well as the chemical building blocks and nutrients needed to support life, had existed for at least tens of millions of years in Gale Crater. The crater once held a lake, the size of which waxed and waned over time. This means that each layer higher up Mount Sharp serves as a record of a more recent era of the Martian environment. Now, the intrepid rover is driving through a canyon that marks the transition to a new region, one believed to have formed as water dried up, leaving behind salty minerals called sulfates. “We see evidence of dramatic changes in the ancient climate of Mars,” said Ashwin Vasavada, Curiosity project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Southern California. “The question now is whether the habitable conditions that Curiosity has found so far have persisted through these changes. Did they disappear, never come back, or come and go for millions of years?’ Curiosity has made impressive progress on the mountain. Back in 2015, the team captured a ‘postcard’ image (see below) of distant stalks. A simple dot in that image is a Curiosity-sized boulder nicknamed “Ilha Novo Destino”—and, nearly seven years later, the rover pulled past it last month on its way to the sulfate-bearing region. The Curiosity team plans to spend the next few years exploring the sulfate-rich region. Within this, they have in mind targets such as the Gediz Vallis channel, which may have formed during a flood late in Mount Sharp’s history, and large cemented fractures that show the effects of groundwater higher up the mountain. This scene was captured by Curiosity on September 9, 2015, when NASA’s Mars rover was several miles from its current position. The circle indicates the location of a Curiosity-sized boulder recently passed by the rover. To its left is the “Paraitepuy Pass,” through which Curiosity is now traveling. Credit: NASA/JPL-Caltech

How to keep a Rover on a roll

What is Curiosity’s secret to maintaining an active lifestyle at the ripe old age of 10? A team of hundreds of dedicated engineers, of course, who work both in person at JPL and remotely from home. They record every crack in the wheels, test every line of computer code before it’s beamed into space, and drill into endless rock samples at JPL’s Mars Yard, making sure Curiosity can safely do the same. “Once you land on Mars, everything you do is based on the fact that there’s no one around to repair it for 100 million miles,” said Andy Mishkin, Curiosity’s project manager at JPL. “It’s all about making smart use of what’s already on your rover.” For example, Curiosity’s robotic drilling process has been reinvented several times since landing. At one point, the drill was offline for over a year as engineers redesigned its use to be more like a hand drill. More recently, a set of braking mechanisms that allow the robotic arm to move or stay in place stopped working. Although the bracket works as usual since the engineers used a set of spares, the team also learned to drill more gently to maintain the new brakes. To minimize damage to the wheels, the engineers pay attention to the recently discovered knife-edge-like danger spots. They developed a traction control algorithm to help as well. The team took a similar approach to managing the rover’s slowly diminishing power. Curiosity relies on a long-life nuclear battery instead of solar panels to keep it going. As the plutonium pellets in the battery decay, they generate heat that the rover converts into energy. Because of the gradual decay of the beads, the rover cannot do as much in a day as it did in its first year. Mishkin said the team continues to calculate how much energy the rover uses each day and has figured out what activities can be done in parallel to optimize the energy available to the rover. “Curiosity is definitely doing more multitasking where it’s safe,” Mishkin added. Through careful planning and engineering teases, the team has every expectation that the lucky rover still has years of exploration ahead of it. More about shipping JPL, a division of Caltech in Pasadena, built Curiosity for NASA and is leading the mission on behalf of the agency’s Science Mission Directorate in Washington.