Drop a photo in the middle of the sky. Heliograph reads when and where it was shot, works out how high the sun was, and turns that light into a Lightroom white balance. Keep the golden hour, or clean it.
Low sun crosses more air: about 2× at 30°, 5.6× at 10°, almost 40× at the horizon. Air scatters blue far more than red, so the longer the path, the warmer the beam. That is golden hour.
After sunset the beam is gone and only the sky is left, which is why blue hour is blue.
Up high there is less air over you and most haze sits in the lowest mile or so. Same sun, cleaner and cooler light: at 10° the model reads about 4100K in Nashville and 4700K in Denver.
Mountains still block the sun early; the model can't see terrain.
Daylight film was fixed near 5500K, so sunsets came out gold. Phones and cameras on auto white balance read the picture and pull it back toward neutral. This works from the sun instead, and the slider decides how much of the mood stays.
Most useful on raw files, where the white balance is still yours to set.