;; JGM-3 Model, as downloaded from U. Texas CSR FTP site (w/ zero tide)
;; $Id: jgm3.desc,v 1.1 2004/01/06 00:36:44 craigm Exp $
{ $
  name: 'JGM-3', $              ;; Title of the model
  type: 'GRAVITY', $            ;; Type of model 'GRAVITY' or 'BFIELD'
  filename: 'JGM3.GEO', $       ;; Model coefficient file name
  reference: 'Tapley, B. D. et al. 1996, "The Joint Gravity Model 3," J. Geophysical Research, 101, 28029', $
  url: 'ftp://ftp.csr.utexas.edu/pub/grav/JGM3.GEO', $
  nmax: 70L, $                  ;; Maximum order (inclusive)
  mmax: 70L, $                  ;; Maximum degree (inclusive)
  normalized: 1, $              ;; Coefficients are normalized (1=yes, 0=no)
  mu: 398600.44150d9, $         ;; GM for central body [m^3/s^2]
  a: 6378136.30d, $             ;; Mean equatorial radius [m]
  tide: 'ZERO', $               ;; Tide system (ZERO, FREE, or MEAN)
  epoch: 1986.0, $              ;; Epoch of model coefficients (Julian year)
  C21: -0.18698764000000D-09,$  ;; C21 coefficient
  S21:  0.11952801000000D-08,$  ;; S21 coefficient
  C20_dot: 0d, $                ;; C20 rate (unitless; yr^-1)
  C21_dot: 0d, $                ;; C21 rate (unitless; yr^-1)
  S21_dot: 0d, $                ;; S21 rate (unitless; yr^-1)
  rowstart: 4L, $               ;; Coefficient starting row (first row = 0)
  nrows: 2552L, $               ;; Number of coefficient rows in file
  ncolrange: [6,7], $           ;; Column range for degree (first col = 0)
  mcolrange: [8,9], $           ;;    "     "    "  order 
  Ccolrange: [10,30], $         ;;    "     "    "  C coefficients
  Scolrange: [32,51], $         ;;    "     "    "  S coefficients
  dCcolrange: [53,63], $        ;;    "     "    "  C std deviation
  dScolrange: [65,75] $         ;;    "     "    "  S std deviation
}