It may seem strange at first, but by the time you get done watching "The Martian," the new movie from director Ridley Scott, you will understand why 20th Century Fox is offering to send you a potato.
Or, if you prefer, you can have a potato sent to a friend.
In the movie, which opens in theatres this Friday (Oct. 2), astronaut Mark Watney finds himself left for dead and alone on Mars. ['The Martian' Movie and NASA: Full Coverage]
"This will come as quite a shock to my crewmates, and to NASA, and to the entire world, but I am still alive," states Watney, played by actor Matt Damon, commenting on his situation. "Surprise."
To survive, Watney must "science the sh*t" out of the Red Planet, which includes attempting to make his food last for longer than planned.
"Right, let's do the math," Watney explains. "Our service mission here was supposed to last 31 sols [Martian days]. For redundancy, they sent 68 sols worth of food, that's for six people. So for just me, that is going to last 300 sols, which I figure I can stretch to 400 if I ration."
"So, I've got to figure out a way to grow three years' worth of food here — on a planet where nothing grows," Watney surmises. "Luckily, I am a botanist. Mars will come to fear my botany powers."
Enter the potatoes.
Without giving away all of the details, the potatoes play an important role in Watney's fate on Mars.
As such, 20th Century Fox has partnered with Mail a Spud (yes, that's a real company) to let fans of the film ship an unpackaged potato through the mail to themselves or to whomever they desire — so long as they live in the United States.
"Send your friend or yourself a potato courtesy of Mark Watney," the studio promotes on the movie's website. "Be one of the first 1000 people to follow the link to mailaspud.com and use the discount code 'MARTIAN' to send a potato for free."
(If you're not quick enough to be included in the first 1,000 fans, Mail a Spud charges $9.99 for each potato.)
But wait, there's more!
Not only do you get a potato — which you could in theory then use to grow even more potatoes, thanks to growing instructions kindly offered by 20th Century Fox — but the potato will come postmarked with a Mark Watney postage stamp.
The $4 custom stamp features a close-up of Mark Watney (Damon) with the slogan, "Bring Him Home."
The stamp has a (possibly inadvertent) connection to the movie, too, by way of the book on which the film is based.
In author Andy Weir's "The Martian," a stamp contributes to how the world marks Watney's status on Mars. In the two months that the Ares 3 crew member is thought to be dead, the U.S. Postal Service (in the book) issues thousands of stamps in his memory.
But, of course, Watney isn't dead.
"We don't print stamps for living people," a representative of the Postal Service tells a news anchor. "So we stopped the run immediately and recalled the stamps."
That prompts the reporter to advise, "If you've got a Mark Watney commemorative stamp, you might want to hold on to it."
But the potato you may want to toss.
See Mark Watney's potato growing instructions from "The Martian" at collectSPACE.com.
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Robert Pearlman is a space historian, journalist and the founder and editor of collectSPACE.com, an online publication and community devoted to space history with a particular focus on how and where space exploration intersects with pop culture. Pearlman is also a contributing writer for Space.com and co-author of "Space Stations: The Art, Science, and Reality of Working in Space” published by Smithsonian Books in 2018. He previously developed online content for the National Space Society and Apollo 11 moonwalker Buzz Aldrin, helped establish the space tourism company Space Adventures and currently serves on the History Committee of the American Astronautical Society, the advisory committee for The Mars Generation and leadership board of For All Moonkind. In 2009, he was inducted into the U.S. Space Camp Hall of Fame in Huntsville, Alabama. In 2021, he was honored by the American Astronautical Society with the Ordway Award for Sustained Excellence in Spaceflight History.