Orbit Fit and Astrometric record for 91554

The following information shows the result of the orbit fit based on Gary Bernstein's method. Most of the information should be self-explanatory. Take special note that while the original Bernstein software works with barycentric coordinates, we convert these results into a heliocentric coordinate system.

# Object: 91554     
# Created Thu May 24 01:36:39 2012
# Orbit generated by ELGB
# -->Covariance matrix from a Bernstein fit
# Fitting   23 observations of   25
# Arc:   6.76y
# First observation: 1999/09/08
#  Last observation: 2006/06/11
# Chi-squared of fit:    39.79 DOF:   40 RMS:  0.23
# Min/Max residuals:    -0.45    0.51
# Exact a, adot, b, bdot, g, gdot:
  2.221908E-05  4.479092E-02  1.073952E-05  1.970509E-02  3.326194E-02  1.825101E-04
# Covariance matrix:
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
#      lat0       lon0       xBary       yBary       zBary        JD0
   -9.527289  -39.070484   -0.408321   -0.151450   -0.900945  2451429.813113
# Heliocentric elements and errors
Epoch:              2451430.5000  =  1999/09/09
Mean Anomaly:            0.27858 +/-     0.000
Argument of Peri:      335.84725 +/-     0.000
Long of Asc Node:      341.69180 +/-     0.000
Inclination:            25.46642 +/-     0.000
Eccentricity:         0.70074863 +/-    0.0000
Semi-Major Axis:    103.47061764 +/-    0.0000
Time of Perihelion: 2451133.0063 +/-       0.0
Perihelion:          30.96372386 +/-    0.0000
Aphelion:           175.97751143 +/-    0.0000
Period (y)             1052.5283 +/-      0.00
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X           23.99397055 +/-    0.0000
Ecliptic Y          -18.94393144 +/-    0.0000
Ecliptic Z           -4.97583631 +/-    0.0000
Ecliptic XDOT         0.00253955 +/-    0.0000
Ecliptic YDOT         0.00269212 +/-    0.0000
Ecliptic ZDOT         0.00159717 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   30.97323717 +/-    0.0000
Geocenter to KBO     30.06442651 +/-    0.0000
# Hcoef:  7.76

The following table shows the complete astrometric record for 91554. The first three columns show the date of observation. The next six columns are RA and DEC. The next column (when provided) is the observed magnitude and filter. The next column is the object name (91554) followed by the observatory code and reference code for the source of the astrometry.

1999 09  08.31237  21 46 29.13   -23 31 21.3   22.5R 91554     568  Ca9937      
1999 09  08.36468  21 46 28.81   -23 31 21.9   22.4R 91554     568  Ca9937      
1999 09  08.42001  21 46 28.47   -23 31 21.8   22.4R 91554     568  Ca9937      
1999 09  10.32683  21 46 17.18   -23 31 37.6   22.4R 91554     568  Ca9937      
1999 09  10.34707  21 46 17.04   -23 31 37.8   22.4R 91554     568  Ca9937      
1999 10  08.23745  21 44 02.43   -23 31 00.7   22.4R 91554     568  Ca9937      
1999 10  08.24916  21 44 02.40   -23 31 00.5   22.7R 91554     568  Ca9937      
1999 11  10.24441  21 43 13.50   -23 18 29.1   22.7R 91554     568  Ca9937      
1999 11  11.29588  21 43 14.31   -23 17 53.0   22.2R 91554     568  Ca9937      
1999 11  13.29373  21 43 16.25   -23 16 42.0   22.6R 91554     568  Ca9937      
2000 05  30.57977  22 02 47.32   -21 03 43.8   22.6R 91554     568  Cb6506      
2000 05  31.59053  22 02 47.25   -21 03 49.8   22.7R 91554     568  Cb6506      
2000 06  01.57429  22 02 47.04   -21 03 56.4   22.6R 91554     568  Cb6506      
2001 07  23.39894  22 08 27.086  -19 20 46.82        91554     568  Cl5551      
2001 07  23.46769  22 08 26.708  -19 20 48.60        91554     568  Cl5551      
2002 11  05.26734  22 08 11.66   -17 38 35.3   22.5R 91554     568  Cl9133      
2002 11  06.28959  22 08 10.86   -17 38 15.3         91554     568  Cl9133      
2004 08  23.14103  22 29 18.66   -13 34 35.4   21.9R 91554     304  Cl4067      
2004 08  23.27769  22 29 17.81   -13 34 38.6         91554     304  Cl4067      
2006 06  11.34509  22 48 29.65   -09 23 35.7   21.9R 91554     250  S~06GZ      
2006 06  11.40707  22 48 29.65   -09 23 35.1         91554     250  S~06GZ      
2006 06  11.41146  22 48 29.65   -09 23 35.1         91554     250  S~06GZ      
2006 06  11.41586  22 48 29.65   -09 23 35.0         91554     250  S~06GZ      
2006 06  21.32949  22 48 24.833  -09 22 44.83  22.5R 91554     304              
2006 06  21.37248  22 48 24.812  -09 22 45.24        91554     304              

The following table shows the residuals to the orbit fit. The first coumn is the point number. The second column is the time, in years, measured from the first observation. The third and fifth columns are the regularized positions used in the orbit fit. The fourth and sixth columns are the residuals, in arc seconds, for RA and Dec respectively.

  1   0.0000      0.00    -0.05       0.00     0.09
  2   0.0001      0.00    -0.02       0.00    -0.45
  3   0.0003      0.00    -0.04       0.00     0.14
  4   0.0055      0.00     0.51       0.00     0.25
  5   0.0056      0.00     0.24       0.00     0.21
  6   0.0819      0.00     0.10       0.00     0.20
  7   0.0820      0.00     0.29       0.00     0.27
  8   0.1723      0.00    -0.23       0.00    -0.11
  9   0.1752      0.00    -0.05       0.00    -0.32
 10   0.1806      0.00    -0.10       0.00    -0.22
 11   0.7263      0.00     0.17       0.00     0.12
 12   0.7290      0.00     0.25       0.00     0.13
 13   0.7317      0.00     0.04       0.00    -0.05
 14   1.8729      0.00    -0.38       0.00    -0.07
 15   1.8731      0.00    -0.43       0.00    -0.22
 16   3.1594      0.00    -0.04       0.00     0.22
 17   3.1622      0.00    -0.07       0.00     0.00
 18   4.9578      0.00     0.14       0.00     0.42
 19   4.9582      0.00     0.06       0.00     0.38
 20   6.7571      0.00     0.36       0.00    -0.19
 21   6.7573      0.00     0.32       0.00    -0.13
 22   6.7573      0.00     0.32       0.00    -0.17
 23   6.7573      0.00     0.32       0.00    -0.11
 24   6.7844      0.00 (   6.11)      0.00 (  -3.67)
 25   6.7846      0.00 (   6.56)      0.00 (  -4.16)

The following table comes from a 10My integration of the orbit of the object. Three columns are shown. The first column is the result of integrating the nominal orbit. The other two columns are based on clones of the nominal orbit that are +/- 3 sigma from the nominal orbit. If all three types agree then the classificiation is deemed secure. The basis for these calculations is described in more detail in AJ, 129, 1117 (2005). Any use made of these calculations should refer to and credit this publication and the Deep Ecliptic Survey Team.

91554    quality flag:2

Type:       CENTAURS  CENTAURR  CENTAURS

axisobj       103.063   103.063   103.063
ecceobj         0.700     0.700     0.700
incobj         25.474    25.474    25.474
qmin           29.672    29.084    29.141
qmax          192.648   188.902   188.189
amean         107.000    97.790    97.933
amin           98.433    91.079    88.715
amax          111.733   110.053   110.005
emean           0.714     0.692     0.685
emin            0.683     0.668     0.649
emax            0.728     0.716     0.711
imean          25.465    24.991    26.290
imin           24.069    23.388    23.941
imax           27.696    27.164    28.013
excite_mean     0.834     0.811     0.816
fracstop        1.000     0.831     1.000
cjmean          2.662     2.664     2.660

libcent 0      -180.0    -180.0    -180.0
libamp  0      -180.0    -180.0    -180.0
libcent 1      -180.0    -180.0    -180.0
libamp  1      -180.0    -180.0    -180.0
libcent 2      -180.0    -180.0    -180.0
libamp  2      -180.0    -180.0    -180.0
libcent 3      -180.0    -180.0    -180.0
libamp  3      -180.0    -180.0    -180.0
libcent 4      -180.0    -180.0    -180.0
libamp  4      -180.0    -180.0    -180.0

kozaimean       112.5     117.7     138.2
kozaiamp        179.9     180.0     180.0