Spatial Debris visualization in Scientific American

Some time ago Scientific American approached me to commission me for the creation of a visualization of spatial debris. And there is a lot of spatial debris floating around the earth. Think of abandoned rockets or broken satellites. The purpose of the visualization I created was to illustratie that there is a huge amount of  spatial debris, and not necessarily to provide an exact representation of it. In fact, not all the required data in order to determine exact position of debris and satellites was available in the dataset I received: right ascension and argument of perigee were missing, so I have used random numbers for those. But all the other data to calculate the orbit was there. In order to calculate the orbits of satellites and debris I had to apply Kepler’s Laws of Planetary Motion.

The graphic has been created in Processing. With all the orbits calculated and the satellites and debris positioned randomly on those orbits, the next thing was to get the color and positioning right. Positioning was rather easy, since it’s just applying some transformations to the image, which resulted in a nice perspective (circles nearby are larger than the ones further away). Coloring was the final step. Initially the idea was to color by country (US, USSR, China and Others), but this resulted in an image with colored dots all over. So to communicate a more focussed message, we decided to show the difference between active satellites (magenta) and spatial debris (black). As a nice extra, the ISS space station is also marked to get an even better sense of the amount of debris.

After completing the project, I played around with the data a little more, just to see if an animated version would have an even greater impact communicating the message. Well, judge for yourself…

Video of talk @ Nerds Unite

About 4 months ago I gave a talk on data visualization at Nerds Unite in Utrecht, NL. I just found out that the video recording of this talk has been published online. The talk itself is in Dutch.

Ghost Counties part of exhibition in Foosaner Art Museum, Melbourne FL

I am honored that my Ghost Counties visualization will be part of an exhibition entitled The Art of Networks that will be on view between March 8-April 8, 2012 at the Foosaner Art Museum in Melbourne, Florida. The exhibit will open on March 8th as a parallel event to the 3rd Workshop on Complex Networks, CompleNet 2012, hosted by the Department of Computer Sciences at Florida Institute of Technology.

In total there will be 14 recent visualizations on networks representing data from different fields, from social networks and migrations to speech cognition and housing issues in the US. The visualizations will be presented both in static and dynamic media: large print formats on the walls and short movies in two computers inside the gallery space.

If you’re in the neighborhood, be sure to drop by!

New website:

I am releasing a new professional website at Except for the blog, the pages of this website at will soon be deactivated. I want to use primarily as my blog. So no worries if you’re doing the D3 tutorials, the blog remains untouched! If you find any peculiarities with the new site, please don’t hesitate to contact me.

In the meantime I am working on quite some interesting visualization projects, but I am unable to share much of it, as these projects are internally used with confidential data. Soon I’ll publish a personal project I’m working.

Data Centric Universe: then and now



For Popular Science I have created a visualization that has been published in both the magazine, and as an interactive version for both the iPad and the web. The visualization shows the known universe of 1950 and todays known universe (2011). Since 1950 modern telescopes have been used, and 93% of the known universe has been discovered after 1950.

The visualization was built in Processing, and then turned into a zoomable image that uses OpenLayers.

Global Agenda Survey 2011

I’ve had the honor to collaborate with the fabulous Moritz Stefaner on a project for the World Economic Forum. We have created several interactive visualizations that allow users to explore the Global Agenda Survey 2011, a survey held each year by the World Economic Forum to discover the most important trends in the world according to its council members.

Except for the network graph, the visualization is compatible down to IE6. We achieved this by using raphael.js, underscore.js. The network has been created in d3.js.

Interview on Fell In Love With Data

Enrico Bertini from Fell In Love With Data has been so kind to post an interview with me about Protovis and D3.

You can read the full interview here.

Thanks Enrico!

Nerds Unite recap

Wednesday I had the honor to give a small presentation about data visualization at Nerds Unite in Utrecht (NL). It was a small group of people who are interested in data, open data, government and of course visualization. After a short introduction I showed some of my work, which was well received. After that Eugene Tjoa gave a talk about creating visualizations for the Central Bureau of Statistics (CBS) in The Netherlands.

It was a great evening with many interesting people. Thanks!

Photo by Sebastiaan Terburg

Guest posts about Eyeo

I am writing 3 daily guest posts about Eyeo Festival on and 1 summary guest post on I’ll update this post with links to each of the individual posts.

Visualizing Europe

Today was one of those days I won’t forget very soon: today was Visualizing Europe day, and many enthusiasts, practitioners, researchers and users of data visualization gathered in Brussels for an inspiring day of talks and meeting interesting and kind people from the data visualization community. The day was divided into 3 sessions:

  1. the power and potential of data visualization
  2. a vision for Europe
  3. where do we go from here?

The first sessions showed some of the best works currently created in data visualization: Santiago Ortiz from Bestiaro showed the power of the visual programming paradigm of Impure can be used to create sophisticated data visualizations in minutes (did I say minutes? seconds!)

Next, Moritz Stefaner showed two of his recent and impressive projects: the Better Life Index project that was recently launched by the OECD. And his previous famous project: Notabilia, which shows deletions on Wikipedia.


Enrico Bertini gave a fantastic talk from a research perspective and explained different approaches of making a data visualization for the public and for the tiny group of people who are actually solving real world problems with data visualization. A quote that was tweeted numerous times immediately: “data visualization is useless, it is indispensable”. He also highly recommends the book: “How Maps Work” (which of course is on my wishlist now!).

Last but not least of this first sessions was Dave McCandless from Information is Beautiful. Dave showed some of his work, and a remarkable quote was: “I disagree with Moritz, I’m not looking for 1000 stories, I’m looking for 1 story that’s interesting”.

After a short coffee break, session 2 started with Gregor Aisch showing how he creates data visualizations as the Open Spending project for the Open Knowledge Foundation. He proposed a new approach for data visualization, namely ‘open data visualization’, which is open source + open data + open to community. An fascinating idea I’d like to learn more about.

Assaf Biderman from the MIT Senseable City Lab impressed us with some of their cutting edge projects they do together with governments and cities, like the Trash Tag project which tracks and visualizes where trash is being transported all over the USA after people have emptied their trash bin. Another project that keeps impressing me is the Copenhagen Wheel, an augmentation to bicycles that allows bikers to track their own performance, and at the same time measures various air conditions of the city. This data is collected and visualized to understand more about the city’s air pollution.

Salvatore Iaconesi from Art is Open Source elaborated on how the artistic world uses data and visualization to change paradigms, for example in supermarkets: while in the supermarket data is visualized on your iPhone and shows the geographic origins of the chemical compounds of your products.

Last but not least, Peter Miller from ITO World had to rush through his slides where he showed some very compelling and sometimes fine-grained user contributions to the Open Streetmap project. It’s impressive to see how user contributions can lead to sometimes more correct maps than non-crowd-sourced maps.

The final session was a discussion between Franco Accordino and Jean-Claude Burgelman from the Europen Commission and Toby Green from the OECD. The main subject was: what did they take from today’s sessions, and what will they do with it. It was very good to see that the value of data visualization was recognized, and that the EU sees data visualization as one possible and valuable way to create new knowledge, which is very important.

Finally, the day was finished by meeting so many people from the data visualization community. It was amazing to meet so many people whom I’ve been in contact with for quite some time now. Thanks for organizing this wonderful day, and everybody who has contributed. It was a memorable experience!

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