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What is a false dawn?

 

What is a false dawn? A false dawn, also called a zodiacal light, which is a strange, eerie, light phenomenon that is visible low in the sky, giving the illusion of an early sunrise or secondary sunset after twilight.

Zodiacal light is best seen just after sunset in spring and before sunrise in autumn, when the zodiac is at a steep angle to the horizon.

However, the glow is so faint that moonlight and/or light pollution outshine it, rendering it invisible.

The brightness of zodiacal light decreases with distance from the Sun. In naturally dark night skies, the glow is visible as a band along the entire zodiac, completely straddling the ecliptic.

It  is a faint, diffuse, and roughly triangular white glow that is visible in the night sky and appears to extend from the Sun’s direction and along the zodiac.

Sunlight scattered by interplanetary dust causes this phenomenon.

The zodiacal light spans the entire sky and largely contributes to the total natural light in a clear and moonless night.

No matter which hemisphere you live in, look to the east before dawn in autumn and to the west after twilight in the spring.

Check out these other articles about this topic:

http://earthsky.org/astronomy-essentials/everything-you-need-to-know-zodiacal-light-or-false-dawn

https://en.wikipedia.org/wiki/Zodiacal_light

 

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