Research and Analysis
The data set was provided by The Meteoritical Society, an organization that has been documenting meteorites since 1933. The data set we received contained the name of each meteorite, the weight, the year when it fell or was found as well as its coordinates. I noticed early that the amount of registered meteorites was very few before 1974. The reason for the increase was that during this time scientists started to discover meteorites in the deserts of the Earth which eventually led to more meteorites being registered.
￼￼In order to get some more knowledge on the subject, I decided to set up a meeting with a professor from the Institute of Geochemistry and Petrology in Zürich. The discussion was very helpful and I definitely got a better understanding of the topic matter. Since the data presented the types of meteorites, one initial thought was to show the origin of them, but unfortunately the documentation of where in space the meteorites originate from is not documented well enough to cover the large part of the approximately 34 000 meteorites that were included in the MS’s data set.
One of the focus points that could give an interesting take on the data is to bring forward the variation of materials of which the meteorites consist. Initial data analysis made it clear that the distribution between the types is quite striking. One of the things that caught my attention when looking at the data was how much of the meteorite types were Chondrites and how few Martian rocks there were. Since the material of the meteorite gives us some hints about its origin, I thought this was a very interesting approach to use when telling a story about this topic. After some research I found that the types can be categorized into ‘stony meteorite’, ‘stony iron meteorite’, ‘iron meteorites’ and in this case also ‘other’ which would include unknown and smaller groups of meteorites. The overall dimensions that I wanted to include in the visualization is the types, the location and the size of the meteorites, which eventually was chosen to be shown in the first part of the visualization on the globe. Different colors were used to clearly indicate the four categories of meteorites and their location shown on a map. The second part would use the same categories but put them in a time perspective and point out the yearly amount of meteorites and what category they belong to.
During the sketching phase I ￼￼wanted to find out how to enhance the chosen set of data and to visually adapt it to the style of the topic itself. As I mentioned earlier the documentation of meteorites didn’t really start until 1974, which means that the chart has very big differences from year to year. This restricted the choice of visualization to some extent because the material amounts vary a lot and some would be barely visible, depending on the style of visualization of course. With the time-frame in mind and since I am still unexperienced when it comes to working with D3.js I decided to go for a static A1-sized poster that would show both of the visualizations. This allowed me to focus more on choosing the right kind of content and figuring out how it could engage the viewer with all the information shown. I started off by figuring out how to show the locations, size of the meteors and their type as one visualization. This would eventually be projected onto a globe showing all the continents and the meteorites as different sized dots and colors. To do this an ‘azimuthal’ equal area projection was used in D3.js that would show all the meteorites and continents at once.
The final result is a poster that shows the locations of all the registered impacts on a globe and the material of these meteorites. On the upper visualization I wanted to highlight some of the meteorites because of the story behind them or how its landing has affected Earth. Some of the meteorites I pointed out were the Cape York Meteorite, which is the heaviest meteorite moved by human force. Another important crater that I wanted to show is the Chicxculub crater that is believed to be formed by the meteorite that eventually led to the extinction of the dinosaurs. The color categories are also used on the second visualization to show the separate amount of a specific material for each year between 1974-2012. The material amounts are separated in different layers to show them in comparison to each other and to make each category more visible. A large scale version of the final poster can be viewed at visualizing.org.
Some of the challenges that I encountered was to choose what parts of the data to use and enhance in order to create an interesting twist to it. In the beginning of the process I wanted to try to combine the original data by the MS with external data but this turned out to be challenging because of the extensiveness of the original set. I also think that by exploring the different ways to tell a story with the original data contributed a lot to my learning and understanding of its diversity. Choosing the colors for the meteorite types, turned out to be harder than expected. Since there are so many meteorites on the map, the colors have to be recognizable and easy to distinguish. To achieve a clear contrast with the colors, I explored with light and dark maps as a background for the dots to see which one is the clearest. After trying out several colors, textures and levels of brightness, I found the version with the darkest map to be the best background for the colorful dots. When displaying the information on the poster the balance of the content was crucial. Showing a large amount of information on one poster puts a lot of focus on the layout and trying to visually avoid “over informing” the reader. Although a lot of information is displayed at once, it is important to achieve an engaging experience for the viewer and to keep them interested. That’s why it is crucial to set up the content so that it allows different layers of information depending on how much information the reader wishes to receive. This means that the information should be easily understood at a quick glance, but still allow room for more in-depth examination.
Taking part in this kind of challenge was a very interesting experience for me, especially since I haven’t worked with data visualization prior to my internship at Interactive Things. By participating in this challenge I got a very good insight of how it is to work with data, making it engaging and easily comprehensible for the viewer. The balance between creating a visually appealing and captivating result and conveying it without compromising the accuracy of the data is something that fascinates me with data visualization and I hope to be able to work with similar challenges again soon!
Martina is currently doing her internship at Interactive Things where she has been working during the last 5 months. She is originally from Helsinki, Finland and is a second year Master student at Aalto School of Art, Design and Architecture.