Earlier this month, the famous meme won a contest sponsored by Lunar Mission One, a commercial space project plotting an unmanned mission to the moon in 2017. As part of the mission, LMO said it will bury an "epic record of life" near the moon`s south pole, as written by the company`s scientists and private donors. In order to draw attention to the crowdfunded project, LMO also promised to include a single picture chosen by Reddit - and announced Astro Sloth as the winner several weeks ago. (Reddit works on an up- and down-voting system, so the winning image was the simply the user submission that got the most up-votes.)

But in a striking commentary on the travails of and digital-age authorship, no one thought to tell Astro Sloth`s creator: the Portuguese artist Pedro Dionisio.

"That`s crazy, this is news to me," Dionisio said by email after being contacted by The Washington Post. "I`ve been spending the last 24 hours ... thinking about how I`m going to write this into my portfolio."

Astro Sloth was never intended as a portfolio piece: certainly, Dionisio didn`t imagine it taking on the life it did. He`s a freelance graphic artist, who usually relies on logo and Web site design to pay the bills. In early 2012, however, Dionisio was practicing Photoshop by superimposing animal heads onto pictures of humans. Astro Sloth was destined for the "recycling bin," he said, but his girlfriend thought it was funny - so he posted the digital artwork on his personal Tumblr, instead.

From Tumblr, of course, Astro Sloth took on a life all his own. Within weeks, fans had dedicated Facebook pages, Twitter accounts and Tumblrs to the sloth, few of them crediting his original maker. In late 2012, a fan changed her father`s desktop backgrounds to Astro Sloth, officially enshrining its meme status. Astro Slothing remains a popular prank: There`s an entire, hilarious Tumblr tag devoted to it.

Dionisio loves that virality, for the most part: He`s particularly fond of the people who have made Astro Sloth tip jars at bars, or gotten Astro Sloth tattoos. Unfortunately, there`s also a downside to watching your artwork become a meme: Dozens of online stores currently sell Astro Sloth merchandise, without crediting or paying Dionisio.

Those T-shirts and mugs and tote bags complete with the prints and T-shirts that Dionisio sells himself - prints and T-shirts that, on a monthly basis, earn the artist almost enough money to cover his rent.

"I often see Astronaut Sloth merchandise that isn`t mine all over the web," he said. "Even though I`d like to have at least credit for it, I`d go crazy if I tried to stop every online vendor from selling my work.

"In the end, I could use the money but hey, it`s still my image that`s going to the moon. How crazy is that?"

Lunar Mission One did not immediately respond to The Post`s questions about how they`re using Dionisio`s work and how they plan to credit him. But the artist isn`t too concerned: He`s just excited to see his work literally taking off.

"I can see how someone can look at Astronaut Sloth and see themselves: a lazy mammal with such big aspirations," Dionisio said. Aspirations like sending your artwork to the moon?

Nah, Dionisio said. Even he never dreamed of that.

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