Earthshine is illumination seen during which phase of the moon?

a. full

b. new

c. last quarter

d. first quarter

Earthshine is even more faint because the moon's "albedo" (a specific kind of reflectivity) is less than Earth's. Even though this dim light is only a reflection it can still illuminate some features of the moon. Earthshine can be best seen during the crescent phases (the 1-5 day period before or after a New Moon).