The “blue hour” is a name for that period where there is light enough to see, but the sun has not yet risen. This time bridges time between darkness and the golden hour, those periods just before sunset and after sunrise when the light differs from ordinary daylight.
As might be assumed from the name, the light at end of day is gilded, even, and without shadow. Entire films have been photographed during the golden hour in smaller latitudes and during the right season when that period lingers longest. Near the equator, the magic might last minutes, but moving toward the poles the Hour might be a full hour because of light bending around the world.
I find some details of Wikipedia‘s “golden hour” entry confusing. We see a noticeable warm light extending long after sunset, but the morning light is clearly blue before the sunrise, become bright and yellow only by contrast once the light hits the sand. That is, perhaps because of the ocean, we see a “golden” light after sunset until dark in the evening and only blue light in the morning. Having learned the term first from cinematographers and second from experience, my understanding may be insufficiently scientific.
In photography, the golden hour is the period of daytime … during which daylight is redder and softer than when the Sun is higher in the sky.
The period of time shortly before sunrise and shortly after sunset is called the “magic hour,” especially by cinematographers.
The period of time shortly before the magic hour at sunrise (or after at sunset) is called the blue hour, when the Sun is at a significant depth below the horizon and residual, indirect sunlight takes on a predominantly blue shade.—Wikipedia
Blue Hour is the title of a book of poetry by Carolyn Forché.
come, love, through burning composed of light converging on my own life from "On Earth"
The blue hour is the time of day my husband and I walk out on the sand, unmasked, and alone. Before sunrise. Before the day begins its busy work.
The blue hour reveals sand newly swept by the sea.
The blue hour is the time of tiny shore birds rising and settling, rising and settling, search and searching.
The blue hour witnesses gulls eating crabs cast onshore.
The blue hour is given over to breaking waves and mere silence underneath.
The blue hour precedes the blind light climbing the coast range and casting brilliance out to sea and finally onto the sand.
The blue hour is cool and clear, damp and dim.
The blue hour.
The pure clean daylight makes an end.
Ah! I have learned how to change text color, single space multiple lines, and indent text—hoorah!