If an observer sees a widespread, pinkish or reddish horizontal band above the eastern horizon after sunset, what phenomenon are they likely observing instead of Venus?

Answer

The Belt of Venus (antitwilight arch)

The Belt of Venus is a broad, colored, hazy illumination opposite the sunset point, caused by sunlight illuminating dust layers, contrasting sharply with Venus, which is a distinct, steady point of light.

If an observer sees a widespread, pinkish or reddish horizontal band above the eastern horizon after sunset, what phenomenon are they likely observing instead of Venus?
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