The Earth’s shadow cone rises in the East after sunset, or in the West before dawn, and can be seen as a dark-blue band, low and broad on the horizon; it is squeezed between the horizon and the anticrepuscular arc. When the sky is especially clear, the upper edge of the shadow reddens and is called the “Belt of Venus”. The anticrepuscular arc is a band located above the antisolar point, while the crepuscular arc lies symmetrically above the sunset area. Both appear after the shadow cone shows up as a yellowish band; later, as the minutes pass, the sky turns completely dark blue, the band dividing the shadow cone and the anticrepuscular arc rises, becoming ever less sharp and more slanted until it disappears.
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