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- Path: sparky!uunet!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!csn!scicom!wats
- From: wats@scicom.AlphaCDC.COM (Bruce Watson)
- Newsgroups: sci.astro
- Subject: Re: Orbit Determination
- Message-ID: <30398@scicom.AlphaCDC.COM>
- Date: 9 Nov 92 20:15:33 GMT
- References: <1992Nov6.135430.6798@serval.net.wsu.edu| <1992Nov8.172831.5995@cbnews.cb.att.com|
- Organization: Alpha Science Computer Network, Denver, Co.
- Lines: 50
-
- In article <1992Nov8.172831.5995@cbnews.cb.att.com| djb@cbnews.cb.att.com (david.j.bryant) writes:
- |While we're on the subject of orbit determination, I'd be interested in
- |any pointers to good reference texts that describe the method of determining
- |orbits from three (or more) visual observations. A step-by-step approach
- |would be best (i.e. taking you through the process of reducing your
- |observations and deriving the orbital parameters).
- |
- |Something with more detail than just "solve the following systems of
- |differential equations" is called for here, as I'm really interested in
- |an algorithmic approach I can carry out myself (and probably implement as
- |a program, just for grins). (Besides, it's been a *long* time since I
- |did any differential equations...)
-
- A good one is _Methods of Orbit Determination_, Escobal, P., Wiley,
- NY, 1965, Chapter 7. Several methods are covered, the algorithms are
- spelled out, and there are good numerical examples and exercises.
-
- A word of warning: You are trying to determine the orbit of
- a low earth satellite with 3 position-3 time methods with optical
- observation. They don't work. See _Celestial Mechanics, A Computational
- Guide for the Practioner_, Taff, L.G., Wiley, NY, 1985, p.216.
- Differential Correction methods are the only ones that work. Taff
- avoids the low satellite case. His examples are for geostationary
- orbits. Even a recent work as _Methods of Orbit Determination_,
- Boulet, Dan, Willmann-Bell, Richmond, VA, 1991 treats the subject
- with an earth satellite which has a semi-major axis of 16000 km.
- With low earth orbits the perturbation of the earth's equatorial
- bulge and atmospheric drag contribute significantly. DC methods
- work but these factors have to be taken into account so instead
- of 6 unknown elements there are more.
-
- One of the problems of orbit determination is that if you are
- the only observer, the best you can do, is to calculate a circular
- orbit solution since the arc under observation is such a small
- portion of the ellipse (unless your observations extend over
- a sufficiently large interval so that the ellipse has rotated
- enough to reveal the eccentricity to the degree of observational
- accuracy.)
-
- In addition to the ones above check out:
-
- Brouvwer and Clemence, _Methods of Celestial Mechanics_, Academic
- Press, 1961.
-
- Baker, _Astrodynamics: Applications and Advanced Topics_, Academic
- Press, 1967.
-
- Bate, Mueller, and White, _Fundamentals of Astodynamics_, Dover, 1971.
- --
- Bruce Watson (wats@scicom) Tumbra, Zorkovick; Sparkula zoom krackadomando.
-