In Brief

Penises on Mars? Grow Up, Internet

Mars Rover Spirit's 'Phallic' Tracks
NASA's Spirit Mars rover created these tracks shortly after touching down in 2004 to execute a turn, not amuse its handlers. (Image credit: NASA/JPL/Cornell)

Has juvenile humor landed on Mars? The Internet is buzzing today (April 24) over a phallic design etched into the Red Planet's surface nine years ago by NASA's Spirit rover, with some folks suggesting the robot's drivers drew it on purpose out of boredom, mischievousness or some combination of the two.

But the truth is much more prosaic. The phallic shape naturally resulted when the six-wheeled Spirit, which was declared dead in 2010, made a turn, as NBC News' Alan Boyle points out. NASA's currently active Mars rovers — Spirit's twin Opportunity and the much larger Curiosity — have also made similar tracks on the Red Planet.

The photo of Spirit's tracks, which was taken by the rover itself, exploded into a bona fide meme after a forum on the popular social-news site Reddit discovered it on Tuesday (April 23). Penis graffiti on Mars? In retrospect, it's surprising it took so long.

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Mike Wall
Senior Space Writer

Michael Wall is a Senior Space Writer with and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.