NASA’s Perseverance rover has finished building a rock deposit on Mars.
It has laid a series of tubes on the ground with a variety of rock and environmental specimens.
The depot will serve as a backup cache that can be returned to Earth in case Perseverance is unable to complete the next phase of its mission.
Scientists want rock samples to be taken home to study in the lab. It will be the best way to determine if life ever existed on the Red Planet.
Photos downlinked from the robot on Monday showed the last of 10 titanium cylinders intended for the depot lying in the dust between the vehicle’s wheels.
The exact position of the tube is carefully documented.
Perseverance was sent to Mars to investigate a 45 km wide bowl called Jezero Crater.
It is a location where a lake is thought to have existed billions of years ago.
It also has the remains of a delta on its western edge.
This is a structure made from the silt and sand dumped by a river as it slows down as it enters a larger body of water.
It’s the kind of feature that may have captured evidence of past microbial organisms.
Perseverance has drilled a mix of volcanic and sedimentary rock that should tell the story of the crater and lake it once contained. Examples of those rocks are now in the depot on a flat piece of land called “Three Forks”.
To be clear, the collection is not the primary cache that NASA wants to return to Earth; it’s more of a “plan B”.
Perseverance stores copies of the Three Forks monsters in the caching system in his abdomen.
The hope is that the rover can deliver these rocks — and others that have yet to be drilled — directly to the mission that’s coming to bring them home.
But NASA can’t risk the scenario where the rover breaks down with all the rocks in it.
The deposit is therefore an insurance policy. It guarantees that something will be available to pick up when the pick-up mission arrives at the end of the decade.
Should the nightmare happen and Perseverance dies, the retrieval mission will be headed straight to Three Forks.
The rover is about to drive to the top of the delta, accompanied by its reconnaissance drone. This mini-helicopter, called Ingenuity, has already started its climb.
Persistence will investigate what appears to be evidence of flooding activity, judging by the large size of some of the boulders scattered across the delta’s summit.
The robot will then move to the rim of the crater where satellite images indicate that there is carbonate-type sedimentary rock. This will be another good place to look for traces of ancient biology.
Perseverance still has over 20 sample tubes waiting to be filled.