NASA’s Mars rover Perseverance finds ‘shark fin’ and ‘crab claw’ in ancient river

Something fishy might be happening on Mars.

NASA’s Perseverance rover captured an image on the Red Planet of two boulders that resemble, respectively, a shark fin and a crab claw.

The car-sized robot arrived on Mars on Feb. 18, 2021, and has been exploring the Jezero Crater, looking for any sign that life on Mars once existed. But these weirdly shaped boulders were an unexpected surprise.

Perseverance is currently traveling across an ancient river delta that was once a 16,000-foot-deep lake.

The photos, which were taken on Aug. 18, 2023, are an example of the phenomenon of pareidolia.

Pareidolia occurs when the brain takes what the eye sees and turns it into a seemingly meaningful image that doesn’t reflect reality — such as when the face of Jesus Christ appears on a piece of burnt toast.

It’s far from the first time something on Mars has been the subject of pareidolia.

One of the most famous examples of the phenomenon is the “Face on Mars,” an image taken by NASA’s Viking 1 spacecraft in July 1976 that appeared to show a sculpture of a face with eyes, a nose and a mouth. NASA explained that the illusion was a result of shadows, but the face nonetheless sparked discussion.

NASA posted the image of the shark fin and crab claw-looking boulders on X (formerly Twitter), as part of their Image of the Week series.

“This rocky duo was spotted hanging out together in a wind-swept area. I spy a … crab claw? Shark fin?” the tweet said. “Comment below with what you see!”

Many people in the replies also saw the underwater animal, but others saw such as a coffee bean, a Stegosaurus, a pair of lips and a turtle head.

Even though Mars was once covered with water, billions of years ago, there’s no evidence that the now-desolate planet ever had any living inhabitants, and these photos don’t change that.