By mapping Mars in the same style as they usually map Earth, cartographers at the British mapping agency Ordnance Survey have made the alien world seem much less so. It's Mars as you've never seen it before — and as a place you might go for an afternoon hike.
The key ingredients to a map with an Earthy feel, according to Wesson, are things like a soft color palate, brown-orange contours, cyan grid lines and a legend. Even components as simple as titles and scale bars (the map has a scale of 1:4,000,000) can subtly make a map seem less spaced-out. And Wesson nixed any super-saturated reds: A map of a valley on Earth wouldn't show bold blues and greens, he reasoned. It would feel more like a traditional map if he muted the shades normally associated with the Red Planet and threw in another color or two to show terrain variation.
In parsing through the open-source NASA data used to make the map, Wesson found the alien geography (martianography?) to pose the biggest challenge.
"Mars is a very different topography to the Earth to map," Wesson said. "The surface is very bumpy but at such a large scale I had vast expanses of land that appeared flat relative to the craters each of several thousands of metres depth, hence the need for different lighting and surface exaggerations. This varying topography led to several attempts by trial and error to find a workable contour interval. Also the contours, which I generated from the elevation data, were very complex and jagged in appearance; trying to smooth them was quite a challenge."
The map is meant as more than just a fun stunt: The idea is to imagine how maps might be designed to help astronauts when they're actually on the surface of Mars. NASA's optimistic plan is to have humans on Mars by the 2030s, and it will be the first time since the moon landings that we've had humans exploring new worlds on foot. Will they use maps like the one above? Perhaps. But Wesson does point out one potential issue with truly Earth-like maps: They're hard enough to handle with bulky gloves on, so a spacesuit would make the task impossible.
"So I imagine even if the content was useful some design thought into the product format would be required," he wrote.