Um Houston, There's A Mars Rock Wedged In The Wheel Of NASA's $2.2B Perseverance Rover
Back on February 25th, 2022, an image from Perseverance captured a stowaway stone lodged into one of the rover's six aluminum wheels. It is believed the rogue stone was picked up while exploring Jezero Crater. The Mars rover has been exploring the area since it landed on the Red Planet back in February of last year.
This is not the first time NASA has had to deal with a rock problem with Perseverance. Last month, a pebble sized piece of debris kept the carousel on the rover from operating properly. Eventually the rover was able to dislodge the debris, which was clogging its sample cache system.
While the image first exposed the fugitive stone on the 25th of last month, a similar image was taken on March 7th (see image below) showing the rock still holding tight in its stowaway location. It now seems that the rock has become a permanent resident of the $2.2 billion rover. While it is unknown as to when the rock first snuck onto the rover, a Jet Propulsion Laboratory (JPL) spokesperson suggests it may have hitched the ride around the first part of February.
In an email to Gizmodo, the JPL spokesperson stated, "It's not perceived as a risk. We've seen these kinds of rocks get 'caught' in Curiosity's wheels from time to time, too." The email continued, "They occur during cross-slope drives, and tend to fall out entirely on their own after a while (there's no particular way to get this rock out of our 'shoe'). These kinds of rocks don't impact driving other than making it a bit noisier."
NASA took note of the wear and tear it was seeing on the Curiosity rover, and upgraded the wheels to prevent the same wear and tear on Perseverance. Perseverance has 20.7 inch (52.2-centimeter) wheels that are capable of withstanding a tag-a-long rock or two. Each of the aluminum wheels are equipped with 48 cleats to improve traction and curved titanium spokes that provide bouncy support.
As of right now, Perseverance is backtracking toward the Octavia E. Butler landing site. While the rover makes its trek back to the landing location, it will be stopping to try and collect more rock samples from the Martian soil. Hopefully, there won't be any more pebbles or debris to cause issues. As for the stowaway stone, it is still along for the scenic ride, as far as we know.
Top Image Credit: NASA/JPL-Caltech
