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Re: Additional altitude correction for Venus
From: Stan K
Date: 2015 May 14, 14:35 -0400
From: Stan K
Date: 2015 May 14, 14:35 -0400
Kermit said:
"If no error from my side, it looks that this extra-correction for Venus is a "phase correction" to account for the appreciable difference between center of mass and center of light of Venus as seen from the Earth. This correction may reach some 15" (arc seconds) for Venus under extreme cases. "Stricto sensu" it concerns all Planets, but in practice it is relevant and appreciable only for Planets inside the Earth Orbit, i.e. Mercury and Venus, with only Venus in practice."
I thought Kermit might have been on to something, but now I'm thinking that this "phase correction" would give a fixed "offset", which would be independent of altitude, so the parallax should still decrease with increasing altitude. Am I thinking too simplistically?
Stan
