Sunset even before being a particular moment of the day is a metaphor.
In literature as in the figurative arts, it is associated with the decline and end (of the day, of light, of life), with the transition from light to darkness: it is the sun’s swan song before it is abandoned, except that it is now universally established that it will nevertheless rise again.
This is why it is so ambiguously fascinating and is universally regarded as a ‘beautiful subject’ par excellence, which has given rise to an endless number of images in painting and photography.
Amidst a few quotations, a few slightly misplaced elements and, where I have succumbed to the temptation to use colour, a few unusually cool tones, I have enjoyed adding a few of my own to the innumerable ranks of crepuscular images, but since I do not believe in resurrections I will close with the words of Catullus:
Soles occidere et redire possunt,
Nobis cum semel occidit brevis lux,
Nox est perpetua una dormienda.