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: 98WX31
# Created Sun Nov 22 02:37:10 2009
# Orbit generated from Bernstein formalism
# Fitting 20 observations of 20
# Arc: 9.29y
# First observation: 1998/11/18
# Last observation: 2008/03/04
Preliminary a, adot, b, bdot, g, gdot:
0.000204 0.025926 0.000006 0.001159 0.025220 0.000000
# Chi-squared of fit: 92.20 DOF: 34 RMS: 0.38
# Min/Max residuals: -1.91 0.50
# Exact a, adot, b, bdot, g, gdot:
1.714658E-05 2.607557E-02 1.618217E-06 1.164010E-03 2.518923E-02 -3.888585E-04
# Covariance matrix:
5.8821E-13 -3.6673E-13 1.5566E-14 -1.5306E-14 3.0633E-13 -1.6386E-12
-3.6673E-13 2.9419E-13 -1.2872E-14 1.2849E-14 -1.6232E-13 1.3391E-12
1.5566E-14 -1.2872E-14 1.3103E-13 -2.4907E-14 7.4500E-15 -6.0755E-14
-1.5306E-14 1.2849E-14 -2.4907E-14 1.0990E-14 -6.8618E-15 6.0528E-14
3.0633E-13 -1.6232E-13 7.4500E-15 -6.8618E-15 3.6634E-13 -8.2267E-13
-1.6386E-12 1.3391E-12 -6.0755E-14 6.0528E-14 -8.2267E-13 6.3303E-12
# lat0 lon0 xBary yBary zBary JD0
1.541782 68.185386 0.202669 0.025694 -0.963038 2451135.917141
# Heliocentric elements and errors
Epoch: 2451130.5000 = 1998/11/13
Mean Anomaly: 352.08641 +/- 0.049
Argument of Peri: 40.43030 +/- 0.062
Long of Asc Node: 37.40425 +/- 0.002
Inclination: 2.96512 +/- 0.000
Eccentricity: 0.11062141 +/- 0.0001
Semi-Major Axis: 45.65558616 +/- 0.0065
Time of Perihelion: 2453607.4117 +/- 15.4
Perihelion: 40.60510097 +/- 0.0072
Aphelion: 50.70607136 +/- 0.0084
Period (y) 308.4957 +/- 0.07
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X 15.30108332 +/- 0.0004
Ecliptic Y 37.66195926 +/- 0.0009
Ecliptic Z 1.06822147 +/- 0.0000
Ecliptic XDOT -0.00264880 +/- 0.0000
Ecliptic YDOT 0.00101992 +/- 0.0000
Ecliptic ZDOT 0.00012531 +/- 0.0000
# Distances at JD0 (AU)
Heliocenter to KBO 40.66555574 +/- 0.0008
Geocenter to KBO 39.69950235 +/- 0.0010
# Hcoef: 6.59
The following table shows the complete astrometric record for 98WX31. 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 (98WX31) followed by the observatory code and reference code for the source of the astrometry.
1998 11 18.41641 04 24 39.16 +23 11 38.2 22.1R 98WX31 695 Ca3608 1998 11 18.48756 04 24 38.78 +23 11 37.3 98WX31 695 Ca3608 1999 01 15.18020 04 19 59.34 +23 00 51.2 22.2R 98WX31 695 Ca3608 1999 01 15.28043 04 19 59.00 +23 00 50.4 98WX31 695 Ca3608 1999 12 28.20885 04 27 34.68 +23 22 20.9 22.5R 98WX31 695 Ca9916 1999 12 28.21610 04 27 34.65 +23 22 21.3 22.1R 98WX31 695 Ca9916 1999 12 31.27627 04 27 20.45 +23 21 48.4 22.3R 98WX31 695 Ca9916 1999 12 31.28462 04 27 20.42 +23 21 48.6 22.1R 98WX31 695 Ca9916 2000 01 05.15228 04 26 59.04 +23 20 58.5 22.6R 98WX31 697 Ca9916 2000 01 05.21591 04 26 58.60 +23 20 57.5 22.8R 98WX31 697 Ca9916 2000 01 05.37209 04 26 58.08 +23 20 56.3 22.4R 98WX31 697 Ca9916 2000 11 23.45582 04 37 00.04 +23 45 39.4 22.0R 98WX31 695 Cc2190 2000 11 23.50006 04 36 59.79 +23 45 39.2 98WX31 695 Cc2190 2000 11 28.37346 04 36 33.30 +23 44 51.7 22.4R 98WX31 695 Cc2190 2000 11 28.41427 04 36 33.07 +23 44 51.3 22.5R 98WX31 695 Cc2190 2000 11 29.35248 04 36 27.95 +23 44 41.9 22.3R 98WX31 695 Cc2190 2003 10 01.57487 04 59 49.52 +24 33 25.8 22.5R 98WX31 568 Ci6852 2003 10 02.53911 04 59 48.13 +24 33 27.3 98WX31 568 Ci6852 2008 03 03.15613 05 16 15.49 +25 08 16.1 98WX31 695 Cy7583 2008 03 04.17287 05 16 15.71 +25 08 13.8 98WX31 695 Cy7583
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 -0.16 0.00 -0.18 2 0.0002 -5.32 -0.16 -0.05 -0.30 3 0.1581 -3914.95 0.26 -2.08 0.00 4 0.1584 -3919.71 0.27 -2.08 0.11 5 1.1083 2489.76 0.10 251.71 -0.41 6 1.1083 2489.42 0.24 252.17 0.05 7 1.1167 2291.12 0.14 250.18 -0.12 8 1.1167 2290.74 0.30 250.44 0.14 9 1.1300 1992.08 0.39 247.05 0.42 10 1.1302 1985.94 -1.91 247.01 0.42 11 1.1306 1978.68 0.21 246.95 0.50 12 2.0152 10392.74 0.09 486.83 -0.11 13 2.0153 10389.31 0.00 487.11 0.14 14 2.0286 10021.65 0.07 490.97 -0.05 15 2.0287 10018.46 0.02 491.02 -0.03 16 2.0313 9947.37 0.13 491.58 -0.12 17 4.8683 29533.27 -0.23 1099.53 -0.57 18 4.8710 29514.17 0.25 1102.93 -0.17 19 9.2888 43511.81 -0.04 2078.12 0.08 20 9.2916 43514.75 0.01 2075.57 0.23
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.
98WX31 quality flag:3 Type: CLASSICAL CLASSICAL CLASSICAL axisobj 45.814 45.834 45.795 ecceobj 0.114 0.114 0.114 incobj 2.966 2.966 2.966 qmin 40.195 39.947 39.929 qmax 50.865 51.147 51.155 amean 45.491 45.504 45.477 amin 45.462 45.443 45.439 amax 45.532 45.551 45.548 emean 0.111 0.114 0.113 emin 0.105 0.105 0.105 emax 0.117 0.123 0.123 imean 2.378 2.492 2.480 imin 1.790 1.896 1.890 imax 2.879 3.029 3.010 excite_mean 0.118 0.122 0.121 fracstop 1.000 1.000 1.000 cjmean 3.103 3.102 3.102 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 173.6 179.8 179.3 kozaiamp 180.0 180.0 179.9