Seeing the “False Dawn”

“Before the phantom of False morning died,
Methought a Voice within the Tavern cried,
When all the Temple is prepared within,
Why nods the drowsy Worshiper outside?”
- from the Rubaiyat of Omar Khayam
The “false morning” in this 900-year-old passage by the Persian poet and astronomer is not a dreamy literary invention, but a real astronomical phenomenon called the “zodiacal light”. Appearing as a faint, eerie glow before sunrise or after sunset, the zodiacal light has likely been seen by stargazers since since antiquity. And it’s well positioned for viewing over the next month or so by observers in both hemispheres.

The picture on this page will help you get a better idea what the zodiacal light is all about. It appears as a tilted cone of light rising 20-30 degrees above the horizon over which the sun is about to rise (or has already set). The light always follows the plane of the ecliptic along which are found the constellations of the zodiac. Hence the name.

The zodiacal light, left, and the Milky Way are seen together in this wide-field astrophoto
Zodiacal light is caused by sunlight reflecting off a lens-shaped disk of dust the lies along the ...