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Re: Calculating accurate apparent-angles between stars
From: Fred Hebard
Date: 2003 Jan 6, 22:36 -0500
From: Fred Hebard
Date: 2003 Jan 6, 22:36 -0500
George, My understanding is that the method you presented at the head of this thread computes an expected observed interstellar distance given a known position and time. This is somewhat the inverse of computing a time from an observed interstellar distance. My understanding is that Borda's, Young's and Bruce Stark's methods address the latter question. In referring to those procedures, I was merely expanding upon your statement that "Unfortunately, doing the reverse calculation, to discover the time and the longitude from a lunar distance, is somewhat more difficult," and implying that they are not appropriate to the "apparent-angle between stars" problem. I must reiterate that I am a complete neophyte in these matters and must perforce bow to your thorough knowledge and experience. I was merely comparing the numerical result from Young's method to that of Stark, and the inputs. I was assuming since both methods addressed the problem of clearing an observed lunar distance of the effects of refraction, parallax, semidiameter, augmentation, etc, they would be methods for solving similar spherical triangles. I know not whether this assumption is correct. The purpose of the comparison was to extend my understanding of the procedures. Fred -- -------------------------------------------------------------------------- Frederick V. Hebard, PhD Email: mailto:Fred@acf.org Staff Pathologist, Meadowview Research Farms Web: http://www.acf.org American Chestnut Foundation Phone: (276) 944-4631 14005 Glenbrook Ave. Fax: (276) 944-0934 Meadowview, VA 24361
