Night sky night sky. Aircraft are also visible at night, distinguishable at a distance from other objects because their lights blink. Night sky The term night sky, usually associated with astronomy from Earth, refers to the nighttime appearance of celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon. Natural light sources in a night sky include moonlight, starlight, and airglow, depending on location and timing. Aurorae light up the skies above the polar circles. Occasionally, a large coronal mass ejection from the Sun or simply
Northern Hemisphere to draw air toward it in a counter-clockwise pattern. Hurricanes and tropical storms (massive low-pressure systems) spin counter-clockwise in the Northern Hemisphere. The shadow of a sundial moves clockwise in the Northern Hemisphere (opposite of the Southern Hemisphere). During the day, the Sun tends to rise to its maximum at a southerly position except between the Tropic of Cancer and the Equator, where the sun can be seen to the north, directly overhead, or to the south at noon dependent on the time of year. When viewed from the Northern Hemisphere, the Moon appears inverted compared to a view from