Definition of "lowsun"

The effect of atmospheric dust is very apparent at lowsun elevations, and the derived Mie scatter polar diagram has a beam width of 48-.

1971, GW Paltridge, SL Sargent, “Solar and thermal radiation measurements to 32 km at low solar elevations”, in Journal of Atmospheric Sciences

"Well," he met the Choco's glare, "we can't very well have him looking like some frithy trail wanderer out for a lowsun stroll, that looks bad on us.”

2017, Joshua K. Sapp, The Shaky Season

Not blue, but a mauve-purple-faded colouring flowering in the dappling and striations of sunlight beneath thin York gums grown in the bank, the slope of the tier below the large red shed which blocks so much lowsun winter light, but now in October, the sun arcs above it, and gets through enough.

2018, John Kinsella, Russell West-Pavlov, Temporariness: On the Imperatives of Place