Wednesday,  February 27, 2013 • Vol. 14--No. 223 • 14 of 35 •  Other Editions

Zodiacal light is glowing pyramid in west after dark

• Moonless evenings in late winter and early spring present the best time of year to see zodiacal light in the Northern Hemisphere evening sky. The light appears when all traces of twilight have left the sky (about 80 to 120 minutes after sunset). It looks like a hazy pyramid of light in the west after true darkness falls.

• This light can be noticeable and easy to see from latitudes like those in the southern U.S. I've seen it many times from the latitude of southern Texas, sometimes while driving a lonely highway far from city lights, up to one hour or so after evening dusk leaves the sky. In that case, the zodiacal light can resemble the lights of a city or town just over the horizon.
• Meanwhile, skywatchers in the northern U.S. or Canada sometimes say, wistfully, that they've never seen it. But a few weeks ago (February 6, 2013) - on our Facebook page - we received the beautiful photo below from Jim Peacock in northern Wisconsin. He captured the zodiacal light over Lake Superior. Sometimes the camera will pick up faint objects that the eye can't see. But Jim said this northern Wisconsin zodiacal light was visible to the eye. He said:
• Yes, it was very visible to the eye … it reached high above the horizon. Was so cool to see over Lake Superior.
• You definitely do need a dark sky location to see the zodiacal light, someplace where city lights aren't obscuring the natural lights in the sky. Remember, the zodiacal light is a pyramid-shaped glow in the west after dark. It's even "milkier" in appearance than the starlit trail of the summer Milky Way. It's most visible after dusk at this time of year because (as seen from the Northern Hemisphere) the ecliptic - or path of the sun, moon, and planets - stands nearly straight up with respect to the horizon after the sun sets in February and March.
• The zodiacal light can be seen for up to an hour after dusk. Unlike twilight dusk, though, there's no rosy color to the zodiacal light. The reddish skies at dusk and

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