Moon Phase Calculator — Plan Night Sky Photography

The moon is extremely bright — even a half-moon washes out faint deep-sky objects and the Milky Way. For the darkest skies, plan shoots within roughly 5 days of a new moon (around 25% illumination or less), or shoot when the moon is below the horizon.

The synodic month (new moon to new moon) is approximately 29.53 days. This means there are roughly 12.4 new moons per year. The waxing phase (growing from new to full) takes about 14.8 days, as does the waning phase.

The Milky Way core will be completely washed out during a full moon. However, you can still photograph bright star clusters, planets, and the moon itself. For Milky Way photography, wait for a new moon window or shoot in the hours before moonrise or after moonset.

This uses a simplified calculation based on the synodic month average. It is accurate to within approximately ±1 day for phase timing and ±5% for illumination. For precise planning, cross-reference with a dedicated astronomy app.