Planets, Dust & Fire

Sean King captured this scene one hour after sunset on March 14, 2012 from 12000ft up on Mauna Loa, Hawaii. Venus and Jupiter are atop a pyramid of Zodiacal Light while hot lava glows at its base.

Image ©Sean King, shown with permission.

The Zodiacal light is a soft pearly cone of light extending upwards from the direction of the sun and along the plane of Earth's orbit projected against the stars, the ecliptic.

Search for it after sunset or before sunrise. The sky must be dark for the Zodiacal light is faint, perhaps the brightness of the Milky Way.   Light polluted skies will not do.

It is best seen from tropical areas when the ecliptic is nearly vertical as here. However, with care it can be seen from the UK or equivalent high latitudes.   Spring after sunset and Autumn before dawn are favoured times.

A disk of dust out to the orbit of Jupiter and perhaps beyond produces it. The dust grains are 0.001 to 0.3 mm across and likely originate from comets.  

The dust grains are large compared to the wavelengths of visible light and consequently scatter sunlight strongly forwards. The glow is therefore brightest near to the sun.

A fainter Zodiacal Band extends around the sky to the gegenschein or counterglow directly opposite the sun.

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