I have a peculiar hobby of collecting Martian hypsometric tinting schemes: those sets of colors that cartographers use to depict elevations on the Red Planet. It’s a fascinating cartographic frontier. While the classic (and somewhat flawed) way of showing Earth’s elevations is to use a color scheme that starts with green lowlands, and then proceeds through some combination of brown/yellow/orange/red until it reaches white in the highest areas, there’s no standard yet for Mars. Maybe centuries from now, one of the schemes below will become that standard.
I also hope this inventory will serve as an inspiration for anyone who’s making a Mars map and doesn’t quite know how to start selecting colors.
A couple notes before we dive in:
- A lot of Mars maps use rainbow color schemes to show elevations. I have excluded those, because they are not cartographically sound. Besides being painful to look at, rainbow color schemes are frequently misleading.
- I’ve included one example of an Earth-style hypsometric scheme, but otherwise avoided them. Mars has its own character, and I think it’s more valuable to see the ways in which mapmakers show it as different than Earth.
- I sampled each of these schemes from the authors’ maps, and then applied them to a uniform map so that they could be compared easily. There may be some small variations from the original, based on my sampling points and color spaces and such. Most maps gave a legend with the colors used, but I often found that those didn’t quite match the colors on the map. So I instead reconstructed schemes based on the final appearance, not the map legend. Note that I also converted some stepped-tone schemes into continuous tones.
Now, let’s meet our contestants! You can click on each image below to view a larger version.
Ralph Aeschliman, 2002
Source Map: Mars Relief and Topographic Coloration Map
This color scheme reminds me a lot of those maps you sometimes see of what Mars might look like if it were flooded. Green-blue fills the lowlands (with a tinge of purple in the deepest depths), until a sharp transition at -2km. After that, rusty browns (reminiscent of the planet’s surface color) transition into cool grey mountaintops.
Carl Churchill, 2019
Source Map: Mars
Churchill starts with a dark grey in the far depths of the Hellas Planitia, which then picks up some saturation to become a dark purple that covers much of the north. It moves from blood red through the oranges, before finishing with a pale yellow (which looks almost like an off-white) at the tops of the peaks of Olympus Mons and the Tharsis Montes. It’s full of rich, bold colors that draw the eye.
Matthew Chwastyk, 2016
Source Map: Various, including the National Geographic Visual Atlas of the World, 2nd Ed.
Much like Rodionova & Brekhovskikh, below, this one is a sort of riff on an Earth-style hypsometric tint, except the saturation is cranked up high, so that it still feels apart from the terrestrial. Cool green and fiery orange, with a little warm brown and white on top. Persons with red-green color vision impairments, however, will have a hard time telling some the lowlands and highlands apart.
Fabio Crameri, Grace E. Shephard, & Philip J. Heron, 2020
Source Map: “The Misuse of Colour in Science Communication” — map is in the “Supplementary Information” section.
Crameri et al. have assembled a series of “Scientific Colour Maps” as part of a campaign to encourage scientists to cease using rainbow palettes. This particular palette is called LaJolla, and is more saturated than some of the other examples in this inventory. A dark, rich reddish-purple anchors the low end, which reminds me of blood oranges.
Kenneth Field, 2016
Source Map: (Is There) Life on Mars?
Kenneth Field’s scheme looks at first like a less saturated version of Churchill’s. It starts with deep purple in the Hellas Planitia, and then proceeds through some nice rusty oranges before settling on a sandy tan (though its context on the map makes it look more yellow). The upper half of the scheme is basically a single color. In Field’s original map, details at the high end are distinguished by contour lines and relief shading, so the clipping seen here isn’t a problem.
Henrik Hargitai, 2016
Source Map: Country Movers
Henrik Hargitai takes an unusual approach, in that his map is at its brightest in the low areas, starting with yellow and turning deep red as elevation increases, and finally finishing off with a little dark pink highlight on the tops of Olympus Mons and the Tharsis Montes.
Chris Herwig, 2012 (a)
Source Map: The Red Planet
This simple black-to-red gradient is the first of two Chris Herwig schemes in this inventory. It’s unusual in that it’s much darker than the rest of the schemes featured here, ready to have light labels placed on top of it. The simple gradient doesn’t allow for a lot of terrain details to pop out, but that’s just fine for a basemap.
Chris Herwig, 2012 (b)
Source Map: Mars Terrain
Herwig’s second scheme is more colorful and overall brighter (though the lowlands are still quite dark). Dark purple-blue transitions into grey, before then moving into warmer colors like yellow and red. In some areas of steep slope, the grey breakpoint is quite noticeable. On the original sourcemap, the grey doesn’t appear until you zoom in. Zoomed out, it is more of a yellow, and there the colors feel a little more continuous. I based my sampled palette on the zoomed-in version.
Daniel P. Huffman, 2017
Source Map: you’re looking at it
My own scheme, which I made just for this inventory (back when there were only four examples, so I needed something to bulk the list up). It is inspired by the colors on the surface of Mars. Due to atmospheric effects, the Red Planet is actually mostly red only if you’re looking at it from space. It’s more brown & tan on the surface, at least if the photos from Curiosity are any indication. I did make the low areas a little reddish just to contrast with the yellow highlands.
Adrian Leung, 2020
This scheme from Adrian Leung uses an unusual diverging approach. The area around zero meters is a faint yellow, and then as you go either higher or lower, you make your way to a rusty brown. Since the highlands and lowlands use the same or similar colors, some other visual cue, like a shaded relief or contour lines, is needed to distinguish them. This is among the more “natural-feeling” palettes I’ve seen; like my own effort above, it appears to be inspired by the planet’s surface.
Eleanor Lutz, 2019
Source Map: Mars
Eleanor Lutz leans heavily on the “Red” in Red Planet. Though it starts with a dark blue-purple in the depths of Hellas Chasma, it quickly turns to a blood red. The palette stays bold and saturated through the lowlands of the Northern Hemisphere, before moving to warm grey for the highlands. It really highlights the contrast of the planet’s two halves, and the upper half of the scheme recalls Earth-based hypsometric tints, in which grey is likewise reserved for the highest elevations.
Daniel Macháček, 2015
Source Map: Topographic Map of Mars
Daniel Macháček, avoiding the Red Planet stereotype, opts for blue (and a bit of purple) in the lowlands, moving through grey into a cool brown for the higher elevations. It’s somewhat like Aeschliman’s scheme, above, with its “flooded Mars” look. It’s a diverging color scheme, starting dark, getting lighter near the middle elevations, and then getting dark again at the mountains (including an interesting band of greenish brown, just below the mountaintops). It highlights the extremes in this way.
Source Map: OPM Mars Basemap v0.2
A super-simple scheme with only three elevation bands, this was designed to serve as a basemap for further Mars maps. The rusty colors are reminiscent of the planet as seen from space. They take up the middle of the luminance range, so both light and dark labels (or other elements) can go on top.
Zh. F. Rodionova & J. Brekhovskikh, 2012
Source Map: Hypsometric Globe of Mars
This scheme keeps the lowlands green, reminiscent of Earth hypsometric tints (though more saturated than most of those), and then shifts quickly into oranges and reds. I have often seen diverging color schemes built from the contrast of green with red/orange used in thematic maps, and this makes the planet’s two hemispheres (which are quite different in elevation) quite visually separate. However, for persons with red-green colorblindness (the most common type), that distinction will be unfortunately muddled.
Tanaka et al., 2014
Source Map: Geologic Map of Mars
Tanaka et al. include a map of Martian hypsometry in the lower right corner of their Geologic Map of Mars. Their color scheme appears to be a simplified version of one you might apply to the Earth, with vegetated green lowlands and barren brown uplands. I mostly want this site to focus on representations of Mars that don’t look back too much to the Earth, but I thought it was good to keep an example of one of these schemes. While I wouldn’t recommend it, it’s certainly possible that, centuries from now, cartographers will decide to use the same green–brown scheme for all planets. Note that, like Field’s scheme above, the upper half of the range is all a single color, so that color transitions can be focused on the elevation range that covers 95% of the planet’s area.
Source Map: Color-Coded Contour Map of Mars
This one strikes me as a blending of an Earth-style hypsometric tint, and a subdued rainbow scheme. As I stated in the preface to this inventory, neither is normally what I’d include here, but I thought the combination was interesting. It covers a pretty broad swathe of the color space: blues, browns, purples, greens, etc. It uses the same (or a similar) sandy-tan at two different elevation levels), which might prompt some confusion without other context cues.
- Most of these schemes do a good job of highlighting the Martian dichotomy — basically, the northern hemisphere is a few kilometers lower than the southern hemisphere.
- Most of the schemes above have a gradient in luminance: that is, the colors transition from light to dark as you change elevation. This means that they should be safe for persons with color vision impairments. However, if you use any of these schemes, you’ll want to run them through something like Color Oracle and probably do some fine-tuning.
- One good thing about a typical Earth hypsometric scheme is that it includes a wide range of colors (greens, yellows, oranges, greys, etc.), which means it can show more detail. Many of the schemes above cover a narrower color range. This is particularly true of those that are inspired by the actual appearance of Mars, which is fairly limiting. Mars is much more uniform in color than the Earth.
- Much of the Martian elevation range is taken up by a few giant mountains. Notice in Kenneth Field’s scheme how little of the map area is tan, and yet that tan covers the entire upper half of the scheme. Each scheme is marked to show the elevations that cover 95% of the planet, which better reflects most of what’s actually seen in the final map.
- These schemes were all designed for different purposes. Some were designed as basemaps upon which to layer other data. Some stood alone. Something to keep in mind when comparing.
- My thanks go to Henrik Hargitai for pointing me in the direction of a number of source maps from which I derived schemes.
Download the Schemes
Interested in trying one of these schemes out? Click to download Photoshop gradient files and QGIS color maps. The latter are basically CSVs, so even if you don’t use QGIS, you can pull the definitions out of them and make use of them in some other way. A few important things to remember about these files:
- I sampled these colors (in Photoshop) from other people’s maps, so my colors might vary slightly from what those authors originally used, especially if I converted their stepped-tone map into a continuous-tone one.
- And, of course, some variation in output may occur due to the color space I’m using, the color space you’re using, and the color space the author used.
- I also likely oversampled, adding more stops to the gradients than were necessary. But the overall aesthetic should match the author’s original intent fairly well, I hope.
- Depending on your Mars DEM, how you processed it, etc., your color breaks might end up in slightly different spots than mine on the map. I’ve loaded different images into Photoshop before and had to adjust how the gradient was applied in order to get the same look.
I’m always looking to expand this catalogue! Please send my way any Martian hypsometric schemes that I haven’t shown here that: (A) are not rainbows, (B) cover all or most of the planet (at least the highest and lowest point), and (C) are not based on an Earth-style hypsometric scheme. By collecting them in one place, I hope to document this little mapping frontier, and perhaps give any future Mars mappers some inspiration for their efforts. So, if this page ever happens to be of use to you, I’d love to hear about it!