Orbit Fit and Astrometric record for 02WL21

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: 02WL21    
# Created Fri Mar 29 01:11:24 2024
# Orbit generated by ELGB
# -->Covariance matrix from a Bernstein fit
# Fitting     25 observations of     25
# Arc:  18.12y
# First observation: 2002/11/28
#  Last observation: 2021/01/11
# Chi-squared of fit:    46.41 DOF:     44 RMS:  0.24
# Min/Max residuals:    -0.47    0.48
# Exact a, adot, b, bdot, g, gdot:
  1.603318E-05  2.437042E-02  5.084960E-07  1.075653E-03  2.461054E-02  6.386763E-04
# Covariance matrix:
  1.9254E-13 -6.3529E-14  3.2084E-15 -2.3214E-15 -1.2933E-13 -1.1034E-13
 -6.3529E-14  3.9526E-14 -2.1973E-15  1.5914E-15  9.0193E-14  7.5623E-14
  3.2084E-15 -2.1973E-15  1.1096E-13 -7.5342E-15 -4.2291E-15 -4.4038E-15
 -2.3214E-15  1.5914E-15 -7.5342E-15  1.0830E-15  3.3061E-15  3.1658E-15
 -1.2933E-13  9.0193E-14 -4.2291E-15  3.3061E-15  4.4239E-13  1.5475E-13
 -1.1034E-13  7.5623E-14 -4.4038E-15  3.1658E-15  1.5475E-13  1.5067E-13
#      lat0       lon0       xBary       yBary       zBary        JD0
    0.336429   75.432022    0.165979    0.005681   -0.968466  2452606.845423
# Heliocentric elements and errors
Epoch:              2452606.5000  =  2002/11/28
Mean Anomaly:           25.16817 +/-     0.047
Argument of Peri:      339.90026 +/-     0.051
Long of Asc Node:       67.80622 +/-     0.001
Inclination:             2.54906 +/-     0.000
Eccentricity:         0.04553854 +/-    0.0001
Semi-Major Axis:     43.37669103 +/-    0.0044
Time of Perihelion: 2445311.3853 +/-      13.5
Perihelion:          41.40137994 +/-    0.0050
Aphelion:            45.35200212 +/-    0.0054
Period (y)              285.6885 +/-      0.04
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X           10.62267436 +/-    0.0003
Ecliptic Y           40.22663811 +/-    0.0011
Ecliptic Z            0.23860171 +/-    0.0000
Ecliptic XDOT        -0.00261362 +/-    0.0000
Ecliptic YDOT         0.00074635 +/-    0.0000
Ecliptic ZDOT         0.00012029 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   41.60624334 +/-    0.0010
Geocenter to KBO     40.63301191 +/-    0.0011
# Hcoef:  7.61

The following table shows the complete astrometric record for 02WL21. 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 (02WL21) followed by the observatory code and reference code for the source of the astrometry.

2002 11  28.34468  04 56 34.85   +22 58 38.9   23.3R 02WL21    568  Cq9881      
2002 11  28.39313  04 56 34.59   +22 58 38.4   23.4R 02WL21    568  Cq9881      
2002 11  28.46548  04 56 34.21   +22 58 38.0   23.5R 02WL21    568  Cq9881      
2002 11  29.33724  04 56 29.57   +22 58 31.4         02WL21    568  Cq9881      
2003 10  03.47532  05 06 06.40   +23 14 46.0   23.7i 02WL21    568  Cq9881      
2003 10  03.53159  05 06 06.30   +23 14 45.9   23.8i 02WL21    568  Cq9881      
2003 10  03.58753  05 06 06.22   +23 14 45.8   23.7i 02WL21    568  Cq9881      
2003 12  16.33458  05 01 00.60   +23 09 00.5   24.5g 02WL21    568  Cq9881      
2003 12  16.36097  05 01 00.46   +23 09 00.1   24.1g 02WL21    568  Cq9881      
2003 12  16.38727  05 01 00.31   +23 09 00.0   24.2g 02WL21    568  Cq9881      
2003 12  17.40625  05 00 54.87   +23 08 52.6         02WL21    568  Cq9881      
2005 11  05.50006  05 16 26.45   +23 34 39.4         02WL21    695  Cq9881      
2006 12  06.48171  05 19 56.89   +23 42 13.1   23.0R 02WL21    250  S~06Ab      
2006 12  06.48611  05 19 56.86   +23 42 13.1         02WL21    250  S~06Ab      
2006 12  06.49051  05 19 56.84   +23 42 13.1         02WL21    250  S~06Ab      
2006 12  06.49491  05 19 56.81   +23 42 13.1         02WL21    250  S~06Ab      
2015 02  18.13741  06 02 41.21   +24 29 13.2   23.4R 02WL21    695  C~1M67      
2015 02  18.18449  06 02 41.08   +24 29 13.3         02WL21    695  C~1M67      
2015 02  18.23098  06 02 40.98   +24 29 13.1         02WL21    695  C~1M67      
2020 12  09.397220 06 44 06.655  +24 25 37.72        02WL21    G37  C~4Twe      
2020 12  09.446100 06 44 06.381  +24 25 38.45        02WL21    G37  C~4Twe      
2020 12  09.493910 06 44 06.179  +24 25 38.43        02WL21    G37  C~4Twe      
2021 01  11.314240 06 41 12.128  +24 28 56.68  23.6G 02WL21    G37  C~4Twe      
2021 01  11.358980 06 41 11.882  +24 28 56.99        02WL21    G37  C~4Twe      
2021 01  11.402030 06 41 11.634  +24 28 57.01        02WL21    G37  C~4Twe      

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    -0.09       0.00     0.03
     2   0.0001      0.00    -0.07       0.00    -0.13
     3   0.0003      0.00     0.08       0.00    -0.00
     4   0.0027      0.00    -0.17       0.00    -0.18
     5   0.8464      0.00    -0.02       0.00     0.25
     6   0.8465      0.00    -0.22       0.00     0.17
     7   0.8467      0.00    -0.11       0.00     0.11
     8   1.0486      0.00     0.02       0.00     0.41
     9   1.0486      0.00     0.07       0.00     0.19
    10   1.0487      0.00    -0.04       0.00     0.27
    11   1.0515      0.00     0.03       0.00    -0.01
    12   2.9381      0.00    -0.30       0.00     0.41
    13   4.0223      0.00     0.48       0.00    -0.47
    14   4.0223      0.00     0.38       0.00    -0.46
    15   4.0223      0.00     0.44       0.00    -0.44
    16   4.0223      0.00     0.35       0.00    -0.42
    17  12.2239      0.00    -0.12       0.00     0.01
    18  12.2241      0.00    -0.30       0.00     0.14
    19  12.2242      0.00    -0.06       0.00    -0.02
    20  18.0316      0.00     0.08       0.00    -0.06
    21  18.0318      0.00    -0.36       0.00     0.36
    22  18.0319      0.00     0.20       0.00     0.05
    23  18.1218      0.00     0.25       0.00    -0.04
    24  18.1219      0.00     0.16       0.00     0.04
    25  18.1220      0.00    -0.09       0.00    -0.15

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.

02WL21    quality flag:3

Type:      CLASSICAL CLASSICAL CLASSICAL

axisobj        43.431    43.431    43.431
ecceobj         0.048     0.048     0.048
incobj          2.545     2.545     2.545
qmin           39.899    39.912    39.906
qmax           46.675    46.684    46.654
amean          43.157    43.157    43.156
amin           42.819    42.818    42.820
amax           43.511    43.513    43.504
emean           0.054     0.054     0.054
emin            0.033     0.033     0.033
emax            0.073     0.073     0.072
imean           1.045     1.045     1.045
imin            0.020     0.020     0.020
imax            1.712     1.712     1.711
excite_mean     0.058     0.058     0.058
fracstop        1.000     1.000     1.000
cjmean          3.087     3.087     3.087

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       163.5     163.5     163.5
kozaiamp        180.0     180.0     180.0