Happy New Year! Not only is it a new year… a quick look out the window or at the Sky Clock reveals that there is a full moon in the sky tonight. Of course, you might not know that if you were locked in a windowless room. Suppose, for example, you were trapped in a room with nothing but a pen knife, a box of paper clips, and access to all the pictures on Flickr. Could you work out when the moon is full? If you are as clever as Jim Bumgardner you wouldn’t have any trouble at all. But since he’s the author of Flickr Hacks, I guess that’s only fair.
Bumgardner took pictures on Flickr that are tagged “full moon” and plotted them according to when they were taken (Flickr knows that because digital cameras encode it in the image). The result is this: A year of full moons. There’s another lovely image where he uses a similar approach to show the seasonal variation in sunset time: A year of sunsets.
This is an example of the informational residue that gets smeared absolutely everywhere on the web. You can learn the most fascinating things these days if you know how to scrape up the data slime. For instance, from the sunset picture mentioned above we can work out the average latitude of Flickr customers. Google Trends can also give you a sense of when the moon is full simply by watching what people search for. Not surprisingly, werewolf searches are somewhat correlated. [Bumgardner’s photos via the Kircher Society]