Orbit Fit and Astrometric record for 21GD9

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: 21GD9     
# Created Fri Dec  3 02:14:04 2021
# Orbit generated from Bernstein formalism
# Fitting     27 observations of     27
# Arc:  71.82d
# First observation: 2021/04/03
#  Last observation: 2021/06/14
Preliminary a, adot, b, bdot, g, gdot:
  -0.000082   0.184610  -0.000101  -0.012614   0.087735   0.000000
# Chi-squared of fit:    28.70 DOF:     48 RMS:  0.18
# Min/Max residuals:    -0.51    0.57
# Exact a, adot, b, bdot, g, gdot:
  2.608036E-05  1.500156E-01 -3.412652E-06 -1.463170E-02  8.221290E-02 -3.189956E-02
# Covariance matrix:
  2.2391E-13 -1.0352E-11  2.5550E-14 -9.1246E-13 -3.8725E-13  1.1626E-10
 -1.0352E-11  8.1791E-09 -2.3995E-11  4.8963E-10  1.2386E-09 -1.5851E-08
  2.5550E-14 -2.3995E-11  1.7506E-13 -2.1310E-12 -3.6659E-12  4.4032E-11
 -9.1246E-13  4.8963E-10 -2.1310E-12  4.0182E-11  7.0908E-11 -1.2517E-09
 -3.8725E-13  1.2386E-09 -3.6659E-12  7.0908E-11  1.9851E-10 -1.4316E-09
  1.1626E-10 -1.5851E-08  4.4032E-11 -1.2517E-09 -1.4316E-09  1.1883E-07
#      lat0       lon0       xBary       yBary       zBary        JD0
   16.295860 -143.424896    0.399232    0.258849   -0.886045  2459307.920361
# Heliocentric elements and errors
Epoch:              2459300.5000  =  2021/03/27
Mean Anomaly:          317.95378 +/-     0.143
Argument of Peri:      179.04760 +/-     0.167
Long of Asc Node:      105.05335 +/-     0.016
Inclination:            16.05426 +/-     0.002
Eccentricity:         0.28320361 +/-    0.0025
Semi-Major Axis:     15.56776833 +/-    0.0299
Time of Perihelion: 2461920.8687 +/-       4.8
Perihelion:          11.15892014 +/-    0.0450
Aphelion:            19.97661651 +/-    0.0551
Period (y)               61.4254 +/-      0.18
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -10.34758373 +/-    0.0016
Ecliptic Y           -7.19189939 +/-    0.0012
Ecliptic Z            3.41306459 +/-    0.0006
Ecliptic XDOT         0.00369207 +/-    0.0000
Ecliptic YDOT        -0.00347929 +/-    0.0000
Ecliptic ZDOT        -0.00076597 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   13.05545540 +/-    0.0014
Geocenter to KBO     12.16354125 +/-    0.0021
# Hcoef: 10.43

The following table shows the complete astrometric record for 21GD9. 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 (21GD9) followed by the observatory code and reference code for the source of the astrometry.

2021 04  03.41956  14 38 10.06   +01 42 56.4   21.8G 21GD9     G96  C~4ib3      
2021 04  03.42982  14 38 09.90   +01 42 56.8   22.2G 21GD9     G96  C~4ib3      
2021 04  03.43494  14 38 09.84   +01 42 58.2   21.9G 21GD9     G96  C~4ib3      
2021 04  07.482866 14 37 24.174  +01 48 24.54  21.9w 21GD9     F51  C~4ib3      
2021 04  07.496238 14 37 24.018  +01 48 25.65  21.7w 21GD9     F51  C~4ib3      
2021 04  07.509674 14 37 23.855  +01 48 26.71  21.6G 21GD9     F51  C~4ib3      
2021 04  07.523082 14 37 23.696  +01 48 27.68  21.8w 21GD9     F51  C~4ib3      
2021 04  08.607350 14 37 11.017  +01 49 53.48  21.3G 21GD9     568  C~4ib3      
2021 04  08.608336 14 37 11.004  +01 49 53.56  21.4G 21GD9     568  C~4ib3      
2021 04  08.609314 14 37 10.994  +01 49 53.67  21.4G 21GD9     568  C~4ib3      
2021 04  13.314991 14 36 14.28   +01 55 55.5   22.1G 21GD9     I52  C~4ib3      
2021 04  13.323901 14 36 14.18   +01 55 56.3   21.1G 21GD9     I52  C~4ib3      
2021 04  13.332798 14 36 14.07   +01 55 57.0   21.5G 21GD9     I52  C~4ib3      
2021 04  13.341671 14 36 13.93   +01 55 57.1   21.5G 21GD9     I52  C~4ib3      
2021 04  19.502334 14 34 56.072  +02 03 20.76  21.5w 21GD9     F51  C~4ib3      
2021 04  19.515000 14 34 55.890  +02 03 21.57  21.5w 21GD9     F51  C~4ib3      
2021 04  19.527654 14 34 55.736  +02 03 22.63  21.4w 21GD9     F51  C~4ib3      
2021 04  19.540338 14 34 55.557  +02 03 23.30  21.4w 21GD9     F51  C~4ib3      
2021 05  30.26966  14 26 20.551  +02 29 05.73  21.6w 21GD9     F51  C~4pbG      
2021 05  30.28148  14 26 20.402  +02 29 05.77  21.6w 21GD9     F51  C~4pbG      
2021 05  30.30519  14 26 20.133  +02 29 05.78  21.7w 21GD9     F51  C~4pbG      
2021 06  06.287933 14 25 09.444  +02 28 25.66  21.3w 21GD9     F51  C~4qqK      
2021 06  06.301191 14 25 09.318  +02 28 25.26  21.3w 21GD9     F51  C~4qqK      
2021 06  06.314515 14 25 09.166  +02 28 25.27  21.3w 21GD9     F51  C~4qqK      
2021 06  14.19399  14 24 01.09   +02 25 42.2   21.7R 21GD9     291  C~4qqK      
2021 06  14.21545  14 24 00.90   +02 25 41.8   21.6R 21GD9     291  C~4qqK      
2021 06  14.23634  14 24 00.71   +02 25 40.9   21.5R 21GD9     291  C~4qqK      

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     0.57       0.00     0.12
     2   0.0000     -2.40     0.07      -0.39    -0.51
     3   0.0000     -3.70    -0.28       0.65     0.41
     4   0.0111   -756.75    -0.10      91.10    -0.04
     5   0.0112   -759.32    -0.07      91.41     0.02
     6   0.0112   -761.98    -0.12      91.63    -0.01
     7   0.0112   -764.55    -0.08      91.79    -0.09
     8   0.0142   -972.09     0.00     112.37    -0.04
     9   0.0142   -972.30    -0.02     112.38    -0.04
    10   0.0142   -972.48    -0.00     112.43    -0.00
    11   0.0271  -1893.81    -0.12     183.75    -0.02
    12   0.0271  -1895.48     0.01     184.03     0.16
    13   0.0271  -1897.27     0.03     184.16     0.20
    14   0.0272  -1899.29    -0.19     183.59    -0.47
    15   0.0440  -3147.21     0.19     231.44     0.13
    16   0.0441  -3150.05    -0.01     231.33     0.01
    17   0.0441  -3152.58     0.11     231.60     0.25
    18   0.0441  -3155.34     0.01     231.38     0.00
    19   0.1556 -10973.76     0.23    -765.85     0.02
    20   0.1557 -10975.90    -0.05    -766.52    -0.05
    21   0.1557 -10979.73    -0.15    -767.80    -0.10
    22   0.1749 -11974.57     0.04   -1143.12     0.09
    23   0.1749 -11976.24     0.16   -1144.10    -0.11
    24   0.1749 -11978.41    -0.21   -1144.81    -0.05
    25   0.1965 -12897.48     0.28   -1624.48     0.09
    26   0.1966 -12900.07    -0.04   -1625.77     0.21
    27   0.1966 -12902.49    -0.26   -1627.53    -0.19

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.

21GD9    quality flag:3

Type:       CENTAURR  CENTAURR  CENTAURR

axisobj        15.564    15.804    15.337
ecceobj         0.279     0.266     0.293
incobj         16.048    16.050    16.046
qmin           10.707    11.460    10.301
qmax           21.702    20.004    20.712
amean          15.942    15.695    15.123
amin           14.844    15.617    14.734
amax           16.416    15.804    15.528
emean           0.309     0.263     0.300
emin            0.248     0.257     0.283
emax            0.328     0.266     0.334
imean          13.914    14.567    14.046
imin           13.038    14.473    13.345
imax           15.330    14.652    14.469
excite_mean     0.392     0.364     0.386
fracstop        0.004     0.000     0.001
cjmean          3.229     3.267     3.303

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       246.5     186.4     192.9
kozaiamp        176.6      12.0      13.5