Fellow Michael Kwartler elucidates why blocks and intersections receive different amounts of sunlight throughout New York City for the New York Times.

“One of the beauties of Manhattan, particularly in spring or fall, is that the grid is about 30 degrees off true North,” said Michael Kwartler, an architect and a shadow consultant based in New York. “That means the intersections tend to be very bright because the sun is going diagonally across them at lunchtime.”

And these intersections, he said, “tend to be brighter than the streets in between, so it creates this really fabulous rhythm in Midtown of light-dark, light-dark.”

Read more: Mapping the Shadows of New York City: Every Building, Every Block, NY Times