When is the Bruce moment?

30 minutes after sunrise to 1 hour or 1 hour to 30 minutes before sunset.

Blues moment refers to a short time when the sky appears dark blue around sunrise or sunset, which occurs about 30 minutes to 1 hour after sunrise or about 1 hour to 30 minutes before sunset. The specific time varies with the season, geographical location and weather. At sunrise, blues usually rises from the horizon with the sun, and the sky turns from dark to bright, showing a dark blue or purple-blue tone.

At sunset, the blues usually appears before the sun goes down, and the sky turns from bright to dark, also showing a dark blue or purple-blue tone.