That would have been my first guess, but I really don't have that much background in orbital dynamics. I'm hoping to get a new tracking platform operational by this weekend so that I can try some imaging, including the zodiacal light and gegenschien. Kim -----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of Chuck Hards Sent: Thursday, September 06, 2007 1:28 PM To: Utah Astronomy Subject: Re: [Utah-astronomy] Bryce Canyon trip - Look for gegenschien please I'm guessing that the dust is at the anti-solar Langrangian point. And if it's glass beads, then imaging might benefit from a polarizing filter... I'm at work now so no time to research the distance question. Good post Kim. On 9/6/07, Kim <kimharch@cut.net> wrote:
At Bryce Canyon NP in June I had an interesting conversation with John Dobson regarding the gegenschein. I've always understood that the source of both the zodiacal light and gegenschein is sunlight reflected from interplanetary comet dust. In his characteristic way, John said, "NO!" According to John, the source is actually reflected sunlight from dust-size fused silica (glass) beads blasted from the surface of the Moon by impacts. Recently, I read a similar explanation at some website that I cannot now locate. Has anyone else heard this theory and know how well accepted it is? Does anyone know of other sources for the theory? (Not that I don't trust John Dobson, of course.) Also, for either theory, does anyone know at what distance the dust/glass is supposed to be from Earth that reflects the sunlight?
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