Mike Bostock (the author of D3.js) is a NYT employee. His name is listed in the final credits for this piece, and a lot of other NYT content. I assume he is often called in to sprinkle some D3 magic onto a lot of their interactive articles.
That globe was a great way to visualize why the sun never sets in the summer above the arctic circle. It would be a great teaching resource especially with some way to adjust the dates.