NASA's Perseverance rover picked up some intriguing-looking objects on Mars this week, which prompted all kinds of speculation on social media. The photo in question was captured on 18 August as Perseverance travels over an "ancient river" and was voted the space agency's top image of the week. On X/Twitter, NASA wrote: "As promised, here’s the new Image of the Week, as voted by you! This rocky duo was spotted hanging out together in a wind-swept area. I spy a…crab claw? Shark fin?" The post was soon flooded with users' takes, with many claiming the two boulders mirrored a shark fin and a crab claw. "I don't know why, but those rocks are really satisfying to look at," one person wrote, while another joked: "I vote for coffee bean." Meanwhile, one realist responded: "That’s literally two rocks." The Perseverance rover landed on 18 February 2021, after a 7-month journey from Earth that started in the summer. The robot has since provided the world with stunning visuals – one of which captured the hearts of social media users. Last year, the rover acquired a pet rock friend on its back wheel, that continued to hitchhike months into its journey. Perseverance likely picked up the large stone in Jezero Crater, which is a 45 kilometer-wide crater thought to have once been filled with water. "The Perseverance rover has a pet rock. NASA says it's breaking hitchhiking records," one person said at the time, while another added: "There's a small rock that's been hitching a ride inside one of the metal wheels of a Mars Rover and I gotta say Perseverance's Pet Rock is a kid's book in the making." Sign up for our free Indy100 weekly newsletter Have your say in our news democracy. Click the upvote icon at the top of the page to help raise this article through the indy100 rankings.