Human WorldSpace

Goodbye, Rock Friend! Mars rover loses pet rock

Help! EarthSky needs your support to continue. Our yearly crowd-funding campaign is going on now. Donate here.

Farewell, Rock Friend

The Mars Perseverance Rover and its Rock Friend have parted ways.

The pair had traveled about 6.2 miles (10 km) across the surface of Mars during a period of 427 sols (439 Earth-days, or more than an earthly year). Space scientists had dubbed it Rock Friend, as they followed along from Earth, after it hitched a ride in the rover’s front left wheel.

People enjoyed watching the rock. Now it’s gone.

Rock Friend first appeared in the rover’s front left wheel on sol 341 (February 4, 2022) of the Mars 2020 Mission. Its arrival onboard was discovered by one of the rover’s Hazard Avoidance Cameras (HazCams).

hollow metal wheel gray rock dust pebbles mars rover perseverance loses pet rock.
Rock Friend, the name given by scientists working on the 2020 Mars Mission, has been riding along in the left front wheel of the Perseverance Rover since early in the mission on Feb. 4, 2022. And then, on April 19, 2023, Rock Friend disappeared, prompting a sad farewell from mission scientists and a range of responses from its fans. Credit: NASA/ JPL-Caltech.

Rock Friend fans emotional, curious

Gwénaël Caravaca is a geologist and sedimentologist, focused on Mars. Caravaca – who has worked since 2019 with the NASA Mars Science Laboratory – has been sharing the adventures of Perseverance and Rock Friend on Twitter. He’s had help from Perseverance mission deputy manager Daniel Zayas.

Many of Rock Friend’s followers were clearly upset by the news of the rock’s sudden departure. Several referenced Wilson, Tom Hanks’ red-faced volleyball companion from the movie Cast Away.

Sadly, Wilson was lost at sea.

Others wondered if Rock Friend had simply reached its destination, somewhere on the Upper Fan near Echo Creek with a view of Belva Crater.

Perhaps, some speculated, Perseverance joined the gig economy, working freelance in the ridesharing industry.

Perseverance not alone in search for life on Mars

Perseverance is based on the design of its still-roving predecessor Curiosity, only bigger.

It is car-sized, about 10 feet long (not including the arm), 9 feet wide, and 7 feet tall (about 3 meters long, 2.7 meters wide, and 2.1 meters tall). But at 2,260 pounds (1,025 kilograms), it weighs less than a compact car. In some sense, the rover parts are similar to what any living creature would need to keep it “alive” and able to explore.

When it’s not picking up otherworldly hitchhikers, Perseverance’s job is drilling into the surface of Mars in search of evidence of ancient microbial life. It has another companion on its odyssey – the Ingenuity Mars Helicopter – and it celebrated a milestone of its own this week (April 19, 2023).

NASA’s Ingenuity Mars Helicopter has completed 50 flights since first taking to the skies above the Red Planet on April 19, 2021, far exceeding its originally planned technology demonstration of up to five flights.

The 2020 Mars Mission isn’t just about finding the tiniest signs of extraterrestrial life. NASA is paving the way for human habitation. Perseverance and Ingenuity play key roles:

These include testing a method for producing oxygen from the Martian atmosphere, identifying other resources (such as subsurface water), improving landing techniques, and characterizing weather, dust, and other potential environmental conditions that could affect future astronauts living and working on Mars.

Bottom line: The Perseverance Mars rover lost its pet rock, Rock Friend, this week after more than a year together.

April 22, 2023
Human World

Like what you read?
Subscribe and receive daily news delivered to your inbox.

Your email address will only be used for EarthSky content. Privacy Policy
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

More from 

Dave Adalian

View All