Cartographer Eric Fischer has spent the last three and a half years tracking over six billion geotagged tweets from Twitter’s public API to create a map visualising those tweets as illuminated dots.

According to Fischer, around 120 tweets are sent per second and 10 million are sent every 24 hours.

Although Fischer managed to track 6,341,973,478 tweets, only 9% are visible on his map, which explains why the map looks so empty. The rest of the tweets that don’t appear on the map are filtered as duplicate or near-duplicate locations.

“For instance, every Foursquare check-in to a particular venue is tagged with the same location, and it doesn’t help the map to draw that same dot over and over,” Fischer says in a blog post. “Showing the same person tweeting many times within a few hundred feet also makes the map very splotchy, so I filter out those near-duplicates too.”

Here’s a screenshot of what unfiltered tweets in a specific location look like.

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You can read up on how Fischer tracked and mapped the tweets on MapBox.

[Source – Forbes, image – Shutterstock]