When the sun has set, no candle can replace it

Twilight fell: The sky turned to a light, dusky purple littered with tiny silver stars

Dusk is just an illusion because the sun is either above the horizon or below it. And that means that day and night are linked in a way that few things are there cannot be one without the other yet they cannot exist at the same time. How would it feel I remember wondering to be always together yet forever apart?