Let's play a game. It's called, "Can you spot the crab in this NASA picture from Mars?" If you look and look again and still can't find that pesky crab, don't be dismayed. The crab (probably) doesn't exist, and so you shouldn't be upset unless you actually do see a crab or two in the picture, in which case you have our condolences. That hasn't stopped the Internet from lighting up with speculation, accusations that NASA is keeping another secret, and the disappointing reality that, apparently, a crab is our first introduction to alien lifeforms.