6 P.M. is the most dangerous time of day to be a pedestrianS

At least in the winter. As the days get longer, the risk tapers off slowly, or gets pushed back an hour or two, as you can see in this chart of pedestrian risk over time. But, it's not just a chart — it's also a map.

It's the work of John Nelson, who has previously done visualizations that take a look at traffic fatalities and a series of "tornado travel maps." In this infographic chart, he plots out the risk of pedestrian accidents, as it changes over seasons and time.

While it's not surprising to see that pedestrian accidents increase as it gets darker, and decrease when the light is better, what is interesting is the way it forms what Nelson calls a "non-geographic map." On Nelson's blog, he explains why and how this kind of unintentional map is created by the data, not just from them:

Amazingly, or not so amazingly to the tougher nuts out there, is that the very roundness of Earth is echoed in the shape of the curve you see in this chart. It's like what I would expect to see from a rough radio telescope signal of some distant planet, only it's our planet. And the signal we see is an emergent reflection of our movements on its curved surface. These traffic events happened in the United States. But the curve would be the same for other Northern Hemisphere places, and it would bend the other way for places in the Southern Hemisphere. Because we live on something that is dynamic, data of our lives often reveals the signal of that dynamic process -a roundabout meta image of Earth. That's a map.