Figure 1. The five lunar phases that have been considered in the analyses (see the text for more details): new moon, waxing/waning crescent, first/third quarter, waxing/waning gibbous and full moon.

The waxing/waning phases and first/third quarter moons (often called a “half moon”) have been grouped together because of their equivalent illumination (http://aa.usno.navy.mil/faq/docs/moon_phases).