An image captured by NASA's Curiosity rover on August 14 is causing quite a stir online, with internet users and bloggers asserting an 'alien thigh bone' has been spotted on the Red Planet. "Normally, I see rocks as rocks," said one commenter, "This can't be a thigh bone, can it?" Others have suggested this find is merely a product of the brain's tendency to spot patterns in otherwise random data. More details at The Independent.