NASA Perseverance Mars rover spots goofy 'butt crack rock'

Butt wait, there's more. Behold the funniest Mars rocks the rover has found so far.

Amanda Kooser
Freelance writer Amanda C. Kooser covers gadgets and tech news with a twist for CNET. When not wallowing in weird gear and iPad apps for cats, she can be found tinkering with her 1956 DeSoto.
Amanda Kooser
2 min read

The Perseverance Mars rover captured this view of "butt crack rock" on June 3.


NASA's Perseverance rover is on Mars to undertake serious science, but we can still have fun with some of the weirder rocks the wheeled explorer has spotted since landing in February. 

The latest entry in the oddball category is what software engineer Kevin Gill -- a "data wrangler" at NASA-JPL -- dubbed "butt crack rock." Insert Beavis and Butthead snickering noises here. The rover snapped a series of views of the rotund item.

Gill patched together a series of partial images taken by the rover on May 31 to reveal the full glory of the rock. Perseverance later snapped a full image on June 3.

There's a long history with Mars and pareidolia -- the human tendency to see familiar objects in random shapes. I once spent hours looking for "faces" in images from NASA's Curiosity rover, just for fun. Space fans have imaginatively seen rocks and formations that resemble a bone, a fish, blueberries and even a spoon.   

With a few flights of fancy and a willingness to be silly, you can find all sorts of entertaining shapes littered across the floor of the Jezero Crater. Here are some of the best so far.


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Software engineer Kevin Gill spotted this brachiosaurus-shaped rock in images taken by the Perseverance rover on Mars.

NASA/JPL-Caltech/Kevin Gill

Gill has a long track record of processing Mars images for the enjoyment of space fans. He spotted an elegant rock snapped by the rover on April 15. 

"Awww, it looks like NASA Perseverance found a tiny fossilized brachiosaurus on Mars," Gill tweeted.

The small stone featured a long "neck," a tiny "head" and a big body that made it look like the famously large vegetation-munching dinosaur. To me, this unusual rock resembles No-Face from the Studio Ghibli movie Spirited Away.

'Butt rock'

Space writer Jason Major noticed a rump-shaped rock in the distance in a rover image from February. "Perseverance probably won't bother going to study it but I hope somebody files this one as 'butt rock,'" Major tweeted cheekily.

Perseverance got a clearer look at "butt rock" a couple of months later. And it still looks a bit like a behind.

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NASA's Perseverance rover got a closer look at "butt rock" on April 22, 2021.


Much like we've seen all sorts of heart-shaped objects in places out in space, perhaps derriere-shaped stones will become hot targets for Perseverance's cameras.

'Odd' rock

The first widely famous rock from the mission dates to late March when the rover eyed a 6-inch-long pockmarked object that NASA described as "odd." Researchers speculated it might be a meteorite or a weathered chunk of bedrock.

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NASA's Perseverance rover snapped a view of this odd rock on March 28. If you look closely just to the right of center, you can see a series of tiny marks where the rover's laser zapped it.


With preceding NASA rovers as a model, we can look forward to more photos of entertaining, intriguing and downright funny Martian rocks as Perseverance makes its way through the crater. 

With other rovers having already spotted a spoon, a pancake, fruit and a "jelly doughnut," we could use a few more food items and table settings to make a complete pareidolia meal.

59 Weird Objects Seen on Mars, Explained

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