10 Minute Map

The challenge: create a map in 10 minutes. The solution: display 10-minute coordinate divisions across the globe. This graticule network shows 3,232 latitude and longitude lines, creating a global grid where each cell at the equator measures roughly 18.5 km.

Grid cells appear different sizes at different latitudes due to Earth's spherical geometry. Longitude spacing decreases with cos(latitude) as meridians converge toward the poles, while latitude spacing remains constant at 18.5 km.