Tabletop Whale

Explaining ventilators for COVID-19

Wed, 01 Apr 2020 00:00:00 -0700

Last week I collaborated with Dr. Sarah Low to explain ventilators in a series of animations. Sarah is an anesthesiology resident at Massachusetts General Hospital, and a leader of CoVent-19 - one of many efforts to address the ventilator shortage during the Covid-19 outbreak. The CoVent-19 organization is run by a team of thirteen medical doctors, including Sarah. Their goal is to teach engineers the basics of medical ventilation, in the hopes that new ventilation solutions can be engineered from existing equipment or repurposed supplies.

Please take a look at the CoVent-19 website for more information! I’m also sharing all of these ventilation graphics to the public domain, so you’re free to use them however you like . But please note that I only illustrated the simplified circuits that Sarah needed (this isn’t a comprehensive explanation of ventilators).

Biology of ventilation

Air moves from our lungs into the bloodstream through tiny, air-filled sacs called alveoli.

Open circuit ventilators

This is a very simple version of a ventilator where waste gas is expelled from the system without recycling.

Closed circuit ventilators

This diagram is more like a modern medical ventilator. A CO2 filter recycles air to reduce waste. An outflow valve controlled by the ventilator releases pressure that builds up as more and more fresh air is added to the closed system.

Biology of ventilation

Air moves from our lungs into the bloodstream through tiny, air-filled sacs called alveoli.

Open circuit ventilators

This is a very simple version of a ventilator where waste gas is expelled from the system without recycling.

Closed circuit ventilators

The Geology of the Moon

Mon, 26 Aug 2019 00:00:00 -0700

This map was one of my favorites, so I’m excited to share the code tutorial for a geologic map of the Moon! Although I already made a geologic map of Mars, this Moon map was much more difficult because the geologic data was split into six different datasets. Each dataset had unique labels (and sometimes different data formats) so I spent a lot of time piecing the data together to create a cohesive map.

One complication with having six datasets instead of one was that some geologic categories were described differently in each dataset, like “Basin Material, Rugged” vs. “Material of Rugged Basin Terrain”. So I decided to combine closely related terms into a single color.

This Moon data was also challenging because the geologic timescales weren’t very precise. Some areas were described with uncertainty - like plains from the “Imbrian or Nectarian” era. And some geologic categories combined many time periods, like craters from “Imbrian, Nectarian, and pre-Nectarian” time periods. I thought it was too complicated to show all these uncertain aggregations in one map, so I decided to omit timescale data entirely. The map features are colored only by geologic category (craters, basins, etc.) and not by age.

The original maps were originally published in the 70’s, and I loved the bright neon color schemes in these historical maps. I tried to keep as many of the same colors as possible, though I re-arranged to save the more extreme colors for smaller or more unusual geologic formations.

The end result is a summarized geologic map rather than a precise replication of the original data. But even though I combined geologic features and didn’t include precise scientific labels, I think the map still works in its limited role as a condensed overview of Moon geology.

Some of the distinctive locations on the Moon. 1: Mare Orientale, a huge impact crater on the far side of the moon. 2: Mare Tranquillitatis, the landing site of Apollo 11 - the first manned landing on the Moon. 3: The far side of the moon. 4: Fra Mauro crater (at center, next to the neon green Fra Mauro highlands), the landing site of Apollo 14 in 1971.

This map is actually the last installment in the Atlas of Space series. I love working with astronomy data and I’m sure I’ll make more maps in the future, but for now I’m taking a break to try and finish my last PhD research project. Thanks for all of your comments and suggestions this summer - I really enjoyed getting to share these maps with you! For those of you going to NACIS meeting this fall, I’m looking forward to talking more about these maps at the conference in the Using Open Data panel. Hopefully I’ll see some of you there!

Sources
Data: Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU). © 2019 Working Group for Planetary System Nomenclature (WGPSN). Planetary Symbology Mapping Guidelines, Federal Geographic Data Committee. LRO LOLA Elevation Model 118m (LDEM GDR). © 2018 NASA PDS and Derived Products Annex. LOLA Science Team. Lunar 5M Geologic Map Renovation. NASA PDS and Derived Products Annex. © 2016 USGS Astrogeology Science Center. Missions to the Moon. © 2019 The Planetary Society. 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 Henrik Hargitai, Oliver Fraser, Michael Ruxton, Chloe Pursey, and Leah Willey for their helpful advice in making this map.

A Topographic Map of the Moon

Mon, 19 Aug 2019 00:00:00 -0700

My next two maps in the Atlas of Space series show the topography and geology of the Moon. These were some of my favorite datasets in the project - the Moon is our closest celestial neighbor, and we know a lot more about the Moon than about our neighboring planets. The Apollo missions even returned several hundred kilograms of lunar rock to the Earth for detailed analysis.

The moon is tidally locked to the Earth, which means that it completes one rotation around its axis in exactly the same time that it takes to circle around the Earth. Because of this, the far side of the moon is never visible from the Earth’s surface. This topographic map shows the near side of the moon in the large central map, as well as the North pole, South pole, far side, and interior in the four surrounding maps.

People have been fascinated by the moon for thousands of years, and lunar events like the full moon or an eclipse are tied to ancient calendars, myths, and celebrations. The lunar cycle can even be seen today in the pattern of Google searches for the word “moon,” which peaks predictably during every full moon.

1: Data layers used to design this map. 2: Google search frequency for the word “moon” in the United States (data from Moon phase dates and Google Trends). Each yellow line shows one lunar cycle in 2018, normalized to the highest and lowest value within each lunar cycle. The turquoise line shows the overall mean.

Sources
Data: Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU). © 2019 Working Group for Planetary System Nomenclature (WGPSN). Earth's Moon In Depth. © 2019 NASA Science Solar System Exploration. LRO LOLA Elevation Model 118m (LDEM GDR). © 2018 NASA PDS and Derived Products Annex. LOLA Science Team. 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.

An Animated Sketch of Jupiter

Fri, 02 Aug 2019 00:00:00 -0700

This week’s map is just for fun! The animated GIF illustrates the storms on Jupiter, but it’s an artistic drawing rather than an accurate representation of the clouds in real time. The majority of the work was done in Photoshop, based on images published from the Cassini spacecraft in 2000 and 2006.

At first I wasn’t planning to map Jupiter, because the surface is constantly changing. We also have much less information about the gas giants compared to the rocky planets closer to Earth. But then I found this awesome video of Jupiter’s clouds, and I decided to edit the film into a repeating cycle.

To make a more detailed design, l I used Cassini’s high-resolution Jupiter map as the background, and placed the lower resolution video on top as a semi-transparent layer. Cassini’s video doesn’t include any data for the North or South poles, so the very top and bottom of this map aren’t animated. You can probably see the discontinuity at about the second bolded latitude line (though it’s not too noticeable because of the low wind speed near the poles).

The high-resolution version of Cassini’s Jupiter map (1) is much more detailed than the video version (2). I combined both of them together to get both detail and animation into the design. The original video doesn’t actually loop, but you can gradually fade the frames at the end of the movie to give the illusion of continuous flow. I also removed the occasional shadowy blotches cast by Jupiter’s moons, and edited the colors and contrast in the video to match the background image.

Although I labeled some of Jupiter’s cloud layers, the storms are constantly shifting and individual bands can move or change color over time. Even the Great Red Spot, a huge storm big enough to swallow the Earth whole, is gradually shrinking and could disappear within our lifetime.

Sources
Data: PIA07783. Cassini's Best Maps of Jupiter (North Polar Map). © 2006 NASA, JPL, and the Space Science Institute. PIA07784. Cassini's Best Maps of Jupiter (South Polar Map). © 2006 NASA, JPL, and the Space Science Institute. PIA02863. Planetwide Color Movie. © 2000 NASA, JPL, and the University of Arizona. PIA07782. Cassini's Best Maps of Jupiter (Cylindrical Map). © 2006 NASA, JPL, and the Space Science Institute. 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.

Constellations from Around the World

Mon, 29 Jul 2019 00:00:00 -0700

Two weeks ago I shared a map of all the stars you can see from Earth, alongside the Western constellations. But the Western constellations are only one of many patterns of stars invented by cultures around the world. This week’s map illustrates the animals, people, and objects imagined in the sky by more than 30 different civilizations.

To make this map I used data from Stellarium, an open-source planetarium software that includes constellations from ancient Dakota, Hawaiian, and Mongolian cultures, among many others. Some of my favorite constellations were the Stars of Water, Rabbit Tracks, and the Hippopotamus, and I also really liked the star names The Oath Star, Lady of Life, and The Hand of the Mouse.

The stars around the Western constellation Orion are one of the busiest places on the map. Some of the individual cultures are highlighted here, including the Chinese constellations in red, ancient Egyptian in turquoise, and Arabic in green. I really liked that each of these cultures included the triple stars in “Orion’s belt”, but still interpreted the star patterns in a completely different design.

The color scheme for this map was inspired by antique roadmaps, like this map of Nebraska from 1898. But this is the only map in the series without a dark background, and I wasn’t quite convinced that a lighter background could work for a star map. I even made two different versions before finally deciding to stick with the original color scheme.

I originally wanted to label the constellations in each culture’s language, but the translations for Stellarium are an ongoing process (that you can help out with, by the way!). I did the best I could by including Chinese labels, which were already fully translated in Stellarium, and by adding phonetic ひらがな labels for Japanese moon signs (I speak Japanese).

This map was definitely one of my favorite designs. At first I was worried that with so many constellation lines, the map would look like a tangled ball of yarn. So I was pleasantly surprised to see that the “ball of yarn” still had a clear pattern - the brightest stars were shared across almost every single culture across the world. I’ll admit that the final map is probably a little too busy to clearly see the individual constellations. But in the end I think the charm of this dataset is seeing the crisscrossing connections shared across the globe, even if the lines are a little entangled.

Sources
Data: Stellarium. © 2019 version 0.19.0. HYG Database version 3. © 2019 David Nash. 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 Nadieh Bremer, Oliver Fraser, Chloe Pursey, and Leah Willey for their helpful advice in making this map.

A Topographic Map of Mars

Mon, 22 Jul 2019 00:00:00 -0700

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.

Sources
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

Mon, 15 Jul 2019 00:00:00 -0700

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.

Sources
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

Mon, 08 Jul 2019 00:00:00 -0700

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.

Sources
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.

The Geology of Mars

Mon, 24 Jun 2019 00:00:00 -0700

This week’s map is an artistic rendition of the geologic map of Mars designed by the USGS. I used the same geology data as the original map, but I added more topographic and label data, redesigned the visual style, and also edited the key for a more general audience.

One of the most difficult parts of making this map was translating the key into plain English. The original USGS map was designed for geologists, so I had to look up almost all of the vocabulary. For example, my abbreviated definition for a caldera rim was “The rim of an empty magma chamber left behind after a volcanic eruption.” The original description was “Ovoid scarp, outlines single or multiple coalesced partial to fully enclosed depression(s); volcanic collapse, related to effusive and possibly explosive eruptions.”

In many cases my translated labels were approximate or less informative than the original, so I decided to also include the original acronyms for each type of geologic unit. These labels can be cross-referenced to the original data to learn more about each type of geologic formation in scientific terms.

Some of the distinctive geologic features on Mars. 1: Olympus Mons, the largest volcano in the Solar System. 2: Valles Marineris, a deep canyon system more than 4000km long. 3: Hellas Planitia, the largest visible impact crater in the Solar System. 4: Mars is divided geologically into the Northern lowlands (pale green) and Southern highlands (brown). Impact craters formed by colliding asteroids and comets (neon yellow) are scattered across the planet.

The individual layers used to make this map. 1-3: Geologic units, geologic contacts, and geologic features from the USGS dataset. 4-5: Hillshade and slope from a different USGS elevation dataset. 6: Nomenclature from NASA IAU. 7-8: Gridlines and a custom 3D effect designed in Photoshop.

I also spent a long time trying out different map projections for this design. I wanted to accurately show how much of the planet was made up of each geologic formation, so in the end I decided to use an Eckert IV equal-area projection. This type of map distorts object outlines, but it preserves the relative area of shapes across the globe. Eckert IV is not great for visualizing the polar regions, so I also added four inset maps to the corners to show each hemisphere of Mars (North, South, East, and West).

To map a 3D object in 2D space, the surface must be transformed using a map projection. There are many different projections, and for the maps in the Atlas of Space series I used Eckert IV, Orthographic, and Plate Carrée projections. To compare these different map projections, you can use a Tissot’s indicatrix - a set of circles of the same size plotted at different places on the globe. All map projections distort space, but you can see that the effects are quite different depending on the projection. 1: Plate Carrée. 2: Eckert IV. 3-5: Orthographic projections centered at different longitudes and latitudes.

Sources
Data: Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU). © 2019 Working Group for Planetary System Nomenclature (WGPSN). Planetary Symbology Mapping Guidelines, Federal Geographic Data Committee. Mars HRSC MOLA Blended DEM Global 200m v2. © 2018 NASA PDS and Derived Products Annex. USGS Astrogeology Science Center. Geologic Map of Mars SIM 3292. Kenneth L. Tanaka, James A. Skinner, Jr., James M. Dohm, Rossman P. Irwin, III, Eric J. Kolb, Corey M. Fortezzo, Thomas Platz, Gregory G. Michael, and Trent M. Hare. © 2014 USGS. Viking Global Color Mosaic 925m v1. © 2019 NASA PDS. Missions to Mars. © 2019 The Planetary Society. 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 Henrik Hargitai, Oliver Fraser, Thomas Mohren, Chris Liu, Chloe Pursey, and Leah Willey for their helpful advice in making this map.

A Topographic Map of Mercury

Mon, 17 Jun 2019 00:00:00 -0700

This week’s blog post is a topographic map of the planet Mercury - the smallest planet and the one closest to the sun. I wanted to map each of the rocky planets in the same style, so this week’s code tutorial actually also includes code for mapping Mars, Venus, and the Moon.

Although Mercury has very few labeled features, I really liked the IAU naming theme for the planet. Craters on Mercury are named after famous artists - including some of my favorites, Lange (named for Dorothea Lange), Gaudí (Antoni Gaudí i Cornet), and Plath (Sylvia Plath).

For this collection of topographic maps, I also designed a cutaway diagram showing the interior layers of each planet. These figures were a little tricky to plot, because the layers on some planets were so thin that they were virtually invisible. To show even the thinnest layers, I designed an adjusted diagram where every layer has a minimum visible thickness:

In the diagram above, the left half shows the actual thickness of each layer, and the right half shows an adjusted version where each layer has a minimum thickness. For Mercury and the Moon there’s actually no difference, but the effect is much stronger for the other planets with a very thin crust or atmosphere. In the end I decided to use the adjusted graph for Earth, Mars, and Venus (with a disclaimer in the key that the figures were not to scale).

Each of the planet core diagrams also has a blurred image of the surface on the outside of the sphere. To make these I used stock images from Stellarium, an open-source planetarium software. I intentionally blurred these images in Photoshop, because a more detailed surface illustration would take the focus away from the cutaway core diagram layers.

The original Stellarium images shown alongside the finished cutaway diagrams for Venus, the Moon, Mercury, and Mars.

This project was a little heavier on the illustration side than my asteroid map last week. I had a lot of fun designing the scrollwork, and I also designed Photoshop overlays to add a 3D effect to the globes and the cutout core diagram. I’m working on a detailed illustration explanation to complement the code tutorial, so in a future blog post I’ll explain the design side of the project!

Sources
Data: Gazetteer of Planetary Nomenclature, International Astronomical Union (IAU). © 2019 Working Group for Planetary System Nomenclature (WGPSN). Mercury In Depth. © 2019 NASA Science Solar System Exploration. Stellarium. © 2019 version 0.19.0. Mercury MESSENGER Global DEM 665m (64ppd) v2. © 2016 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, Jennifer Hsiao, Chloe Pursey, and Leah Willey for their helpful advice in making this map.

Tabletop Whale

Explaining ventilators for COVID-19

Biology of ventilation

Open circuit ventilators

Closed circuit ventilators

Biology of ventilation

Open circuit ventilators

Closed circuit ventilators

The Geology of the Moon

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A Topographic Map of the Moon

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An Animated Sketch of Jupiter

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Constellations from Around the World

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A Topographic Map of Mars

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The Western Constellations

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An Animated Map of the Earth

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The Geology of Mars

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A Topographic Map of Mercury

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