Moon Calendar 2020
This visualization presents a year-long moon calendar for 2020, showing each day’s lunar phase as a small orthographic projection of the moon arranged by month and day. User clicks trigger an animated red ring that expands and fades around the current day’s moon. The code uses D3 v5 with SVG, `d3.geoPath` and `d3.geoOrthographic` for rendering, and computes phases from a simple formula based on a fixed new moon reference time. Axis labels are generated with `d3.axisLeft` and `d3.axisTop`.