The sunlight reflects off the nearest surface of the UFO.
The UFO has tilted, not rotated.
"AI Overview
When sunlight reflects off the nearest surface of an object, it's a phenomenon known as reflection, and the degree to which it's reflected depends on the surface's albedo and other factors. Albedo is the measure of how much sunlight a surface reflects, ranging from 0 (perfect absorber) to 1 (perfect reflector)."
