A NASA image of Mars being passed around on social media over the weekend has imaginations running wild.
The photo shows a stone formation in front of what may be a kind of cave. Some say it looks a bit like a crab monster straight out of a science fiction tale.
Here's a closer look:
But don't worry, future missions to Mars are unlikely to encounter any crab monsters.
Seth Shostak, Senior Astronomer and Director of the Center for SETI Research, said he gets images showing formations such as this one about once a week.
"Those that send them to me are generally quite excited, as they claim that these frequently resemble SOMETHING you wouldn't expect to find on the rusty, dusty surface of the Red Planet," he said via email. "It's usually some sort of animal, but occasionally even weirder objects such as automobile parts. Maybe they think there are cars on Mars."
He said it's really just a phenomenon called pareidolia, or the brain's ability to make shapes out of random objects -- like seeing animals in clouds.
"Far from being a vision defect, pareidolia has a lot of survival value if you need to quickly spot predators in the jungle, for instance," he wrote.
"Recognizing a crab in a landscape filled with wind-weathered rocks is no more surprising -- nor more significant -- than seeing a winking face in a semi-colon followed by a parenthesis. ;) "
That means that this, taken from the same image, isn't a Martian sand yeti -- or maybe a very lost wampa -- peeking out from behind some rocks either:
There may be no evidence for life on Mars -- yet -- but you can do more than scan images to help the hunt for extraterrestrial intelligence. UC Berkeley's SETI@Home allows you to put your computer's spare processing power to work analyzing narrow-bandwidth radio signals from space.
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