Zodiacal Light and the False Dawn
Credit & Copyright:
Yuri Beletsky
(ESO)
An unusual triangle of light will be particularly bright near the eastern horizon before sunrise
during the next two months for observers in Earth's northern hemisphere.
Once considered a false dawn, this triangle of light is actually
Zodiacal Light, light reflected from
interplanetary dust particles.
The triangle is clearly visible toward the left of the frame taken from the
Paranal
Observatory in Chile
in July.
Zodiacal dust
orbits the Sun
predominantly in the same plane as the planets: the
ecliptic.
Zodiacal light is so bright this time of year because the
dust band is oriented
nearly vertical at sunrise,
so that the thick air near the horizon does not block
out relatively bright reflecting dust.
Zodiacal light is also bright for
people in Earth's northern hemisphere in March and April just after sunset.