Animals are classified as "matutinal" or "vespertine" depending on whether they are active during this period of time.
This phenomenon's namesake "wedge" appears red in color due to backscattering from a light source whose zenith angle is in between 10 and 20 degrees. The scientific term for "God rays," in which rays stream through clouds, takes their name from this phenomenon. Animals are classified as "matutinal" or "vespertine" depending on whether they are active during this period of time. The "nautical" definition for this period of time states that it begins or ends when the (*)  Sun is 12 degrees below the horizon. The adjective crepuscular refers to this period of time, which in the morning occurs after a dawn but before a sunrise. For 10 points, name this period of time in which the Sun is not visible but is still illuminating the Earth, exemplified by the period immediately preceding dusk.
This phenomenon's namesake "wedge" appears red in color due to backscattering from a light source whose zenith angle is in between 10 and 20 degrees.
twilight  