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Re: (meteorobs) zodiacal light on Jan 03, 2001
Bob Lunsford notes:
>If you have really dark skies you might try for the zodiacal band, which
>can be seen at any time of night. This faint band stretches the entire
>length of the zodiac...
The gentle, ever-so-subtle glow of the Zodiacal Band stretching across
the sky is indeed one of the finer thrills of a really dark site.
Another target somewhat brighter, and so often accessible from sites
where the Zodiacal Band is too faint to see, is the famed Gegenschein
or "counterglow": this is a "cloud" of faint gray light (some call it
pearly) which surrounds the point on the Zodiac that lies immediately
opposite the sun in the night sky. When the ZB is well visible, I've
also noted the Gegenschein to be as much as 20 degrees wide and 10 or
15 degrees North-South. But generally, sky conditions will make the
GS seem a good deal smaller than that.
In any case, from a quite dark site, if you hit just the right time of
night and of the year (so that nothing is lost in twilight or in the
Milky Way's "glare"), you can test your eyes and your skies with the
"triple header" of interplanetary dust - the Zodiacal Light rising in
the East (or West), then merging cleanly into the Zodiacal Band which
stretches across the rest of sky, finally spearing the counterglow on
the other side of the sky from the bright cone of Zodiacal Light!
And even more interesting is to note the often apparently irregular
shapes of all three of these features! Strange indeed to imagine the
possible causes of this visual effect...
Quite a diversion for the meteor observer blessed with good skies. :)
Clear skies and happy sky-watching,
Lew Gramer
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