NASA/JPL-Caltech/Malin Space Science Systems Derivative work Oliver Giddings is a five-year-old British boy who dreams of one day becoming an astronaut.

And he certainly has the first step down: a curiosity for space.

This year, Giddings wrote to the Royal Mail asking how much it would cost to send a Christmas card to Mars.

Right now there's no one to send a Christmas card to on Mars right now — except the robotic rovers exploring the surface, like NASA's Curiosity rover shown right. However, humankind might one day colonize the red planet, and then Christmas cards might not sound so bizarre.

Instead of ignoring Giddings inquiry, the postal service employees contacted one of the few agencies in the world who know exactly how expensive it is to land payloads on Mars: NASA.

Scientists at NASA's Kennedy Space Center in Florida estimated that sending a card that weights 100 grams (0.22 pounds) to Mars would cost Giddings about £11,600 (British pounds), or $17,253, the Daily Mirror reported.

This amount includes the cost of the rocket fuel necessary to get the card on course to Mars as well as the weight of the card, since payload weight is one of the cost drivers of rocket launches.

While $17,000 is nothing compared to NASA's multi-billion dollar Mars rover missions, it's still an obscene amount of money for a card.

When the Royal Mail sent NASA's response to Giddings, he said, "Wow! That's a lot of money. It's very expensive to send a letter to Mars. You would need so many stamps!"

If we do send humans to live on Mars in the future, digital Christmas cards will be faster and cheaper. That said, NASA gave Giddings something invaluable this year: the gift of knowledge.