The blue hour refers to a phase of twilight when the Sun is so far below the horizon that the light’s blue wavelengths dominate. Because the blue hour is a colloquial term, it doesn’t have an official definition similar to dawn, dusk, and the three phases of twilight.
In other words…
The best time of day, and most evocative for lyrical expounding.
Blue Hour
Powder skies, pale blue
Deepen as day is ending:
Look, sunset beckons.
Briefest window: light
Scattered across atmosphere,
Blue most prominent.
Hinterland between
Day and night: moments altered
By diffused twilight.
Calm produces still,
Thoughtful consideration:
Reflect, what’s to come.
Arrival, darkness
Black illuminating; stars
Turn backdrop deeper.
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