A Topographic Map of Mars
July 22 2019 · Link to the Open-Source Code
This week’s map is a topographic map of Mars! I already shared the code to make these topographic maps a few weeks ago, so for this blog post I decided to write a better description of how I illustrated the ornamental borders and decided on a design style for the map collection. Although style design was the least technical part of the project, I think it actually took just as much time - if not more - than any of the code for individual maps.
For this project I wanted to combine large datasets with the hand-crafted design style of artists like William Morris or Alphonse Mucha. To organize my thoughts I collected a big folder of inspiration images from sources like the New York Public Library Digital Database.
When I started this project I initially wanted to design different border decorations for every topic. I sketched a collection of 18 different repeated patterns, each meant to go alongside a unique astronomy theme like planets, galaxies, space missions, or satellites. But as the project continued I realized there was so much data that the detailed borders made the maps look too cluttered. In the end I removed all of the borders and designed just one scrollwork illustration to wrap around rounded map projections like this Mars map. In these round maps I thought the shift from detailed map to blank paper was a bit too abrupt, so this was a good compromise between data-heavy and illustrative design styles.
I like to start my projects by sketching outlines and graphs using pencil and paper. Most of my sketches aren’t as neat as this example, but it’s much easier for me to experiment with shapes when I’m drawing in a physical sketchbook. For color palettes I jump straight into digital design, where it’s much faster to make small changes in hue or saturation.
The 14 color schemes I designed in the beginning of the project. Each color palette is shown in several different ways, because I wanted to design versatile color schemes that could work as discrete elements, or as pieces of a complex pattern, or as a gradient in topographic maps. The color schemes marked with an asterisk were used as gradients for topographic maps, but the rest either didn’t make into the final collection or were only used as part of larger color palettes, such as the geologic maps.
With the borders removed from the project, the scrollwork surrounding the round maps were the most illustration-heavy part of the map collection. When I paint decorations like these in Photoshop, I begin each design as a solid white shape and then gradually break away pieces into detailed chunks. Next, I brush away pieces of each section with the brush eraser tool until the pieces look like a fully-shaded monochrome design. I wait to add color until the very last step, where I use many different colors and overlay layers for a richer effect.
To design the scrollwork border I first sketched a rough outline of the shapes in pencil. I tried a couple different iterations of leafy scrolls before finally picking a less botanically inspired design. In this snapshot the top half shows the sketching process - where I tried out many different shapes - and the bottom half shows the actual illustration process, beginning with very large sections of solid color and ending with many small, shaded segments.
I’ve updated all of my tutorials for decorated maps with a section on design, as well as a piece of the scrollwork illustration file. The file includes the original layers as reference for those of you want to use a similar style in your own projects.
- Data: Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU). © 2019 Working Group for Planetary System Nomenclature (WGPSN). Mars In Depth. © 2019 NASA Science Solar System Exploration. Stellarium. © 2019 version 0.19.0. Mars HRSC MOLA Blended DEM Global 200m v2. © 2018 NASA PDS and Derived Products Annex. USGS Astrogeology Science Center. Reference texts: Astronomy, Andrew Fraknoi, David Morrison, Sidney C. Wolff et al. © 2016 OpenStax. Fonts: The labels on this map are typeset in Moon by Jack Harvatt. The title font is RedFlower by Type & Studio. Advice: Thank you to Oliver Fraser, Henrik Hargitai, Chloe Pursey, and Leah Willey for their helpful advice in making this map.
The Western Constellations
July 15 2019 · Link to the Open-Source Code
This week’s map shows every single star visible from Earth, on the darkest night with the clearest sky. The map also includes all of the brightest galaxies, nebulae, and star clusters from W.H. Finlay’s Concise Catalog of Deep-sky Objects. I illustrated the familiar Western star patterns - or asterisms - in blue and gold, as well as the scientific constellation boundaries in red.
Although the constellation boundaries are officially defined, asterisms are up for interpretation. So I actually used two different asterism datasets: Stellarium for the central map, and Western Constellation Lines by Marc van der Sluys for the illustrations in the bottom right corner. I thought it was interesting to show the range of interpretations for the same shapes (Sagittarius and Lepus are particularly unique across the two datasets).
Some of my favorite sections of the finished map. Orion and Canis Major were particularly difficult to label, because there were so many galaxies and stars all clustered around the same place in the sky. The tiny Greek letters next to the brightest stars are Bayer designations - stellar identifiers often used to label stars. After plotting all of these different elements in Python, I tweaked the label positions in Illustrator and added a glow effect in Photoshop to make the map look like the night sky.
This map plots the size of each star based on its magnitude, or the relative brightness as seen from Earth. Star magnitude doesn’t measure the actual size of the star, so it’s possible for a small star to have a larger magnitude than a massive star if the smaller star is closer to Earth. The star colors are somewhat close to the true colors, but they’re exaggerated to make the difference between similar stars easier to see on the dark background.
To illustrate the constellations shown on the bottom of the map, I used the 1824 card series Urania’s Mirror as a reference. The original engraved constellation cards were punched with small holes so that each star appeared to shine when the cards were held up to a light.
To update these illustrations from Urania’s Mirror, I first mapped each constellation using the modern HYG star database. Then I adjusted pieces of the Urania’s Mirror illustrations to fit next to the modern star alignments. I also increased the contrast between shapes and removed some confusing details, like the quiver on the centaur’s back in this example. The full-size map already shows the actual magnitudes of each star, so I decided to use a more artistic style for these illustrated stars. Each star is drawn as a sunburst with many rays, and the stars are all the same size so the constellation pattern is easier to see against the illustrated background.
- Data: Concise Catalog of Deep-sky Objects. W.H. Finlay. © 2003 Springer. Urania's mirror, or, A view of the heavens. Richard Rouse Bloxam, Sidney Hall, and Jehoshaphat Aspin. © 1824 Samuel Leigh. Unicode Character Table. © 2019 Sergei Asanov and Oleg Grigoriev. Stellarium. © 2019 version 0.19.0. HYG Database version 3. © 2019 David Nash. Western Constellation Lines. © 2005 Marc van der Sluys. Catalogue of Constellation Boundary Data. A.C. Davenhall and S.K. Leggett. © 1989 Royal Observatory Edinburgh. Used with permission. Reference texts: Astronomy, Andrew Fraknoi, David Morrison, Sidney C. Wolff et al. © 2016 OpenStax. Fonts: The labels on this map are typeset in Moon by Jack Harvatt. The title font is RedFlower by Type & Studio. Advice: Thank you to Oliver Fraser, Marc van der Sluys, Chloe Pursey, and Leah Willey for their helpful advice in making this map.
An Animated Map of the Earth
July 8 2019 · Link to the Open-Source Code
This is one of the very few animated maps I made for my space cartography project! NASA publishes many Earth datasets at monthly time scales, and this GIF uses one frame per month to show the fluctuating seasons. The animation focuses mainly on data about Arctic sea ice and vegetation, but it was hard to choose - NASA has many other beautiful seasonal datasets, like fire, temperature, or rainfall.
The NASA Earth Observations website includes data on seasonal fire incidence (1), vegetation (2), solar insolation, or the amount of sunlight (3), cloud fraction (4), North Pole ice sheet coverage (5), and processed satellite images (6). My own map (7) combines the ice sheet data and the Blue Marble satellite images. The NEO database also has many more interesting datasets not shown here, like rainfall, chlorophyll concentration, or Carbon Monoxide.
To match the rest of the space map collection, I decided to emphasize the natural features of the Earth. So I didn’t include any country borders, country names, or other political information (though I did include large cities because I thought they counted as interesting physical features). Instead I tried to use colors and labels that emphasized the capes, oceans, deserts and forests of the world. I also used the bottom two corner maps to show the changes in cloud cover and temperature throughout the year.
In addition to data from NASA, I also used outlines and labels from Natural Earth. Natural Earth is a public domain map dataset with many useful features, and for this animation I used Natural Earth coastlines and labels for cities, ice sheets, lakes, and other large natural areas. I also used data from the USGS to map the Earth’s tectonic plates.
As an unrelated note, I’ve also gotten several emails asking for high-resolution digital wallpapers of my space maps - so here they are! These are completely free, and you can download the ZIP files of five different wallpapers for 4:3 resolution, 16:9, 16:10, and double monitors.
- Data: Blue Marble: Next Generation Topography and Bathymetry © 2004 NASA Earth Observations. Sea Ice Concentration and Snow Extent, Global (1 Day - SSM/I/DMSP) © 2017 NASA Earth Observations. Cloud Fraction (1 Month - AQUA/MODIS) © 2018 NASA Earth Observations. Solar Insolation (1 Month) © 2018 NASA Earth Observations. Earth True Color (1 Day - NPP/VIIRS) © 2019 NASA Earth Observations. Natural Earth 1:10m Cultural Vectors Populated Places © 2019 Natural Earth v4.1.0. Natural Earth 1:10m Physical Vectors River Centerlines © 2019 Natural Earth v4.1.0. Earth In Depth © 2019 NASA Science Solar System Exploration. Earth's Atmospheric Layers © 2010 USGS Spatial Services. Tectonic Plate Boundaries © 2019 . Reference texts: Astronomy, Andrew Fraknoi, David Morrison, Sidney C. Wolff et al. © 2016 OpenStax. Fonts: The labels on this map are typeset in Moon by Jack Harvatt. The title font is RedFlower by Type & Studio. Advice: Thank you to Chloe Pursey and Leah Willey for their helpful advice in making this map.