Curiosity set out to answer the question: Did Mars ever have the right environmental conditions to support tiny life forms called microbes? Early in its mission, Curiosity’s science tools found chemical and mineral evidence of past habitable environments on Mars. Continue exploring the rock record of a time when Mars may have been home to microbial life. Credit: NASA
Despite signs of wear and tear, the intrepid spacecraft is about to begin an exciting new chapter of its mission as it climbs a Martian mountain.
Ten years ago, on August 5, 2012, a jetpack landed NASA’s Curiosity rover on the Red Planet. This was the beginning of the SUV-sized rover’s search for evidence that Mars had the conditions necessary to support microscopic 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 found that the answer is yes and have been 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 traveled nearly 29 kilometers and climbed 625 meters (2,050 feet) as it explores Gale Crater and the foothills of Mount Sharp within it. The Mars rover has analyzed 41 rock and soil samples, using a suite of scientific instruments to learn what they reveal about Earth’s rocky sibling. Its success has 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 10th anniversary of the agency’s Curiosity Mars rover on the Red Planet with a double-sided poster that lists some of the intrepid explorer’s inspiring achievements. Download it for free here. Credit: NASA/JPL-Caltech
A reward of science
It’s been a busy decade for Curiosity. The roving explorer has studied the red planet’s skies, capturing images of bright clouds and drifting moons. Its radiation sensor is helping NASA figure out how to keep future astronauts safe by measuring the amount of high-energy radiation they would be exposed to on the Martian surface.
But most significantly, Curiosity has discovered that liquid water, as well as the chemical components and nutrients necessary to sustain life, were present for at least tens of millions of years in Gale Crater. The crater housed a lake, the size of which increased and decreased over time. This means that each layer above 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, thought to have formed as water was drying up, leaving behind salty minerals called sulfates.
“We’re seeing evidence of dramatic changes in the ancient Martian climate,” said Ashwin Vasavada, Curiosity’s project scientist at NASA’s Jet Propulsion Laboratory (JPL) in Southern California. “The question now is whether the habitable conditions Curiosity has encountered so far persist through these changes. Did they disappear, never to return, or did they come and go for millions of years?
Curiosity has made amazing progress on the mountain. In 2015, the team captured a “postcard” image (see below) of distant buttes. A simple blob within this image is a Curiosity-sized rock nicknamed “Ilha Novo Destino,” and nearly seven years later, the rover passed by 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 zone. Within it, they have targets in mind 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 further up the mountain .
This scene was captured by Curiosity on September 9, 2015, when NASA’s Mars rover was many miles from its current location. The circle indicates the location of a Curiosity-sized rock that the rover recently passed. To the left of this is “Paraitepuy Pass”, which Curiosity is now traveling through. Credit: NASA/JPL-Caltech
How to keep a Rover rolling
What is Curiosity’s secret to maintaining an active lifestyle into 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 catalog each and every crack in the wheels, test every line of computer code before it’s sent into space, and drill endless rock samples at JPL’s Mars Yard, making sure Curiosity can safely do the same .
“As soon as 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 acting project manager at JPL. “It’s about making smart use of what’s already in 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 look more like a hand drill. Most recently, a set of braking mechanisms that allow the robotic arm to move or stay in place stopped working. While the arm has been working as usual since the engineers hired a set of spares, the team has also learned to drill more gently to preserve the new brakes.
To minimize wheel damage, engineers are keeping an eye out for treacherous spots like the knife-edge “gator-back” terrain they recently discovered. They developed a traction control algorithm to help as well.
The team has taken a similar approach to managing the slowly diminishing power. Curiosity relies on a long-life nuclear battery instead of solar panels to keep rolling. As the plutonium pellets in the battery break down, they generate heat that the rover converts into energy. Because of the gradual degradation of the pellets, the rover cannot do as much in one day as it did in the first year.
Mishkin said the team continues to budget 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. “The curiosity is definitely to do more multitasking where it’s safe to do it,” Mishkin added.
Through careful planning and engineering hacks, the team has every expectation that the valiant rover still has years of exploration ahead of it.
More information about the mission
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.