43 lines
1.5 KiB
Go
43 lines
1.5 KiB
Go
// Copyright 2022 HE Boliang
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// All rights reserved.
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package gofa
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const (
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VERSION = 1.18
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)
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/*
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ASTROM Star-independent astrometry parameters
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(Vectors Eb, Eh, Em and V are all with respect to BCRS axes.)
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*/
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type ASTROM struct {
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Pmt float64 /* PM time interval (SSB, Julian years) */
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Eb [3]float64 /* SSB to observer (vector, au) */
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Eh [3]float64 /* Sun to observer (unit vector) */
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Em float64 /* distance from Sun to observer (au) */
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V [3]float64 /* barycentric observer velocity (vector, c) */
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Bm1 float64 /* sqrt(1-|v|^2): reciprocal of Lorenz factor */
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Bpn [3][3]float64 /* bias-precession-nutation matrix */
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Along float64 /* longitude + s' + dERA(DUT) (radians) */
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Phi float64 /* geodetic latitude (radians) */
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Xpl float64 /* polar motion xp wrt local meridian (radians) */
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Ypl float64 /* polar motion yp wrt local meridian (radians) */
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Sphi float64 /* sine of geodetic latitude */
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Cphi float64 /* cosine of geodetic latitude */
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Diurab float64 /* magnitude of diurnal aberration vector */
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Eral float64 /* "local" Earth rotation angle (radians) */
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Refa float64 /* refraction constant A (radians) */
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Refb float64 /* refraction constant B (radians) */
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}
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/*
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LDBODY Body parameters for light deflection
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*/
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type LDBODY struct {
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Bm float64 /* mass of the body (solar masses) */
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Dl float64 /* deflection limiter (radians^2/2) */
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Pv [2][3]float64 /* barycentric PV of the body (au, au/day) */
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}
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