Despite signs of wear, the intrepid spacecraft is about to start an exciting new chapter in its mission as it climbs a Martian mountain.
Ten years ago today, a jet pack of NASA’s Curiosity spacecraft landed on the Red Planet, beginning the voyage of an SUV-sized explorer to search for evidence that Mars, billions of years ago, had the conditions to support microscopic life.
Since then, Curiosity has traveled nearly 18 miles (29 kilometers) and ascended 2,050 feet (625 meters) as it explores Gale Crater and the slopes of Mount Sharp within. The craft analyzed 41 samples of rock and soil, relying on a suite of scientific instruments to find out what it reveals about Earth’s rocky brother. And it prompted a team of engineers to devise ways to reduce wear and keep the rover spinning: In fact, Curiosity’s mission was recently extended for another three years, allowing it to continue among NASA’s fleet of vital astronomical missions.
bounty of knowledge
It’s been a busy decade. Curiosity studied the skies of the Red Planet and captured images of bright clouds and drifting moons. The rover’s radiation sensor lets scientists measure the amount of high-energy radiation that future astronauts on Mars will be exposed to, helping NASA figure out how to keep them safe.
But most importantly, Curiosity has determined that liquid water as well as the chemical building blocks and nutrients needed to support life have been present for at least tens of millions of years in Gale Crater. The crater once contained a lake, which has diminished in size and dwindled over time. Each layer higher on Mount Sharp is a record of a more recent era of the Martian environment.
Now, the intrepid craft is traveling through a valley marking the transition to a new area, which is believed to have formed as the waters dried up, leaving behind salty minerals called sulfates.
“We’re seeing evidence of dramatic changes in the ancient Martian climate,” said Ashwin Vasavada, Curiosity project scientist at NASA’s Jet Propulsion Laboratory in Southern California. “The question now is whether the habitable conditions Curiosity has found so far persisted through these changes. Did they disappear, never to return, or did they come and go through millions of years?”
Curiosity made amazing headway up the mountain. Back in 2015, the team snapped a “postcard” photo of a distant tendon. Just spot inside that image is a Curiosity-sized boulder called “Ilha Novo Destino” — and nearly seven years later, its rover slammed into it last month on its way to the sulfate-bearing region.
The team plans to spend the next few years exploring the sulfate-rich area. Within it, they have targets in mind such as the Gediz Vallis Canal, which may have formed during a flood late in Mount Sharp’s history, and large plaster fractures showing the effects of groundwater atop the mountain.
How to keep the rover in roll
What is Curiosity’s secret to maintaining an active lifestyle at the age of 10? A team of hundreds of professional engineers, of course, work in person in the JPL and remotely from home.
They catalog every crevice in the wheels, test every line of computer code before it is broadcast into space, and dig through endless rock samples at JPL’s Mars Yard, ensuring that Curiosity can safely do the same.
“Once you land on Mars, everything you do depends on the fact that there is no one around to fix it for 100 million miles,” said Andy Myshkin, Curiosity project manager at JPL. “It’s all about 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 be more like a handheld drill. Recently, a set of braking mechanisms that allow the robotic arm to move or stay in place has stopped working. Although the lever has been operating as normal since the engineers used a bunch of spares, the team also learned to dig in more gently to maintain the new brakes.
To minimize damage to the wheels, engineers keep an eye on treacherous spots like the knife-edged terrain they’ve recently discovered, and they’ve developed a traction control algorithm to help, too.
The team took a similar approach to managing the slowly dwindling rover power. Curiosity uses a long-life nuclear-powered battery instead of solar panels to keep rolling. When the plutonium pellets in the battery decompose, they generate heat that converts the rover into energy. Because of the gradual decay of the pellets, the rover cannot do as much in a day as it did during its first year.
Myshkin said the team continues to budget how much power the rover uses each day, and has discovered activities that can be done in parallel to improve the power available to the rover. “Curiosity certainly does more multitasking where it’s safe to do so,” Mishkin added.
Through careful planning and engineering stealth, the team had every expectation that the brave rover still had years of exploration ahead of it.
More about the mission
The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, built Curiosity for NASA and is leading the mission on behalf of the agency’s Science Mission Directorate in Washington.
For more information about Curiosity, visit:
http://mars.nasa.gov/msl And the https://www.nasa.gov/mission_pages/msl/index.html
News Media Communication
Jet Propulsion Laboratory, Pasadena, California.
Karen Fox / Alana Johnson
NASA Headquarters, Washington
email@example.com / firstname.lastname@example.org