For more than two years, NASA’s Perseverance rover has been roaming Mars, drilling for rock samples that may hold clues to ancient life on the Red Planet, but the six-wheeled robot can only travel so far. Luckily, the rover recently got some extra help from a river that once flowed on the surface of Mars.
In late June, NASA’s Perseverance rover sealed its 20th rock sample in an airtight titanium tube nestled inside its belly. This particular sample likely came from elsewhere on Mars and was deposited along the rover’s path by a river during Mars’ distant past, NASA revealed this week.
The Martian rover is currently exploring the top of a fan-shaped pile of sedimentary rock that stands 130 feet (40 meters) tall. Perseverance drilled the sample from an outcrop composed of tiny chunks of other rocks in an ancient riverbed in Jezero Crater, although the rock sample likely came from a place on Mars that the rover may never visit.
“Pebbles and boulders found in a river are messengers from afar,” Ken Farley, Perseverance project scientist from Caltech in Pasadena, said in a statement. “And while the water that created the Martian riverbed that Perseverance is currently exploring evaporated billions of years ago, the story carried by those waters remains fresh, stored in conglomerate rock.”
Perseverance collects its samples using a drill attached to the rover’s arm. The samples are sealed in a tube and moved into the Adaptive Caching Assembly System, where they are processed. Once it has collected all its samples, the rover will stow them away in a safe location on Mars.
NASA wants to later retrieve those samples through a joint mission with the European Space Agency called Mars Sample Return. The plan to bring back the first rocky samples from another planet is highly complicated, and it involves an orbiter, lander, two helicopters, and a rocket all working together to transport the rocks from Mars to Earth.
There are concerns that the mission will go way over budget and face delays in its launch. The Mars Sample Return project is currently under some serious heat from the Senate, which is threatening to cancel the mission altogether if NASA isn’t able to provide a year-to-year funding profile for the mission. In April, NASA Administrator Bill Nelson revealed that the mission would need an additional $250 million in the current fiscal year, plus another $250 million in 2024, in order to stay on track for launch in 2028.
For now, Perseverance is still fulfilling its primary purpose, collecting rock samples from the surface of Mars in hopes that one day those rocks will make their way to Earth where they can be probed for signs of ancient life.
Mars is a dry and arid desert today, but scientists believe the Red Planet may have once hosted habitable conditions during its early history. Using data and images collected by the Perseverance rover, scientists recently found evidence of organic molecules on Mars. This doesn’t suggest that Mars had some form of life on it yet, but it does provide more evidence that the planet was once habitable.
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