Orbit Fit and Astrometric record for 21LW43

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: 21LW43    
# Created Tue Apr  1 01:11:25 2025
# Orbit generated from Bernstein formalism
# Fitting     18 observations of     18
# Arc:   1.37y
# First observation: 2021/06/09
#  Last observation: 2022/10/21
Preliminary a, adot, b, bdot, g, gdot:
  -0.000032   0.022852   0.000015   0.009994   0.023101   0.000000
# Chi-squared of fit:     0.55 DOF:     30 RMS:  0.03
# Min/Max residuals:    -0.06    0.06
# Exact a, adot, b, bdot, g, gdot:
  1.560532E-05  2.297287E-02  6.654406E-06  1.023485E-02  2.327827E-02 -5.784628E-04
# Covariance matrix:
  2.5121E-13  2.1273E-13 -4.4724E-14  6.8206E-13  4.9140E-13  4.8590E-11
  2.1273E-13  1.2614E-12 -1.9707E-13  3.0033E-12  1.6991E-12  2.1475E-10
 -4.4724E-14 -1.9707E-13  2.0824E-13 -1.1655E-12 -4.0334E-13 -7.5598E-11
  6.8206E-13  3.0033E-12 -1.1655E-12  1.6254E-11  6.1443E-12  1.1511E-09
  4.9140E-13  1.6991E-12 -4.0334E-13  6.1443E-12  2.9920E-12  4.4020E-10
  4.8590E-11  2.1475E-10 -7.5598E-11  1.1511E-09  4.4020E-10  8.2673E-08
#      lat0       lon0       xBary       yBary       zBary        JD0
    0.925181  -72.886190    0.491598    0.014067   -0.884370  2459374.942811
# Heliocentric elements and errors
Epoch:              2459370.5000  =  2021/06/05
Mean Anomaly:          355.63761 +/-     1.395
Argument of Peri:       10.80320 +/-     2.766
Long of Asc Node:      284.44141 +/-     0.000
Inclination:            23.98708 +/-     0.005
Eccentricity:         0.30515411 +/-    0.0019
Semi-Major Axis:     62.94637073 +/-    0.0725
Time of Perihelion: 2461580.9279 +/-     707.1
Perihelion:          43.73802714 +/-    0.1315
Aphelion:            82.15471432 +/-    0.1540
Period (y)              499.4181 +/-      0.86
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X           12.43851417 +/-    0.0009
Ecliptic Y          -42.04579850 +/-    0.0031
Ecliptic Z            0.69400316 +/-    0.0001
Ecliptic XDOT         0.00256213 +/-    0.0000
Ecliptic YDOT         0.00088582 +/-    0.0000
Ecliptic ZDOT         0.00120232 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   43.85256488 +/-    0.0029
Geocenter to KBO     42.95851390 +/-    0.0032
# Hcoef:  9.84

The following table shows the complete astrometric record for 21LW43. 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 (21LW43) followed by the observatory code and reference code for the source of the astrometry.

2021 06  09.44201  19 13 42.195  -21 25 33.88  26.2r 21LW43    266  C~6Ip2      
2021 06  09.52601  19 13 41.836  -21 25 33.97  26.2r 21LW43    266  C~6Ip2      
2021 06  09.61426  19 13 41.459  -21 25 34.04  26.2r 21LW43    266  C~6Ip2      
2021 06  17.43605  19 13 07.273  -21 25 44.42  26.1r 21LW43    266  C~6Ip2      
2021 06  17.50053  19 13 06.975  -21 25 44.52  26.1r 21LW43    266  C~6Ip2      
2021 06  17.57953  19 13 06.610  -21 25 44.64  26.1r 21LW43    266  C~6Ip2      
2021 07  05.35106  19 11 42.008  -21 26 23.00  25.8r 21LW43    266  C~6Ip2      
2021 07  05.43951  19 11 41.567  -21 26 23.23  25.8r 21LW43    266  C~6Ip2      
2021 07  05.52517  19 11 41.139  -21 26 23.44  25.8r 21LW43    266  C~6Ip2      
2021 09  06.23258  19 07 30.377  -21 27 58.63  26.6r 21LW43    266  C~6Ip2      
2021 09  06.31281  19 07 30.203  -21 27 58.54  26.6r 21LW43    266  C~6Ip2      
2021 09  06.39352  19 07 30.029  -21 27 58.44  26.6r 21LW43    266  C~6Ip2      
2022 10  20.21696  19 12 37.642  -20 41 34.40        21LW43    266  C~8ebm      
2022 10  20.26058  19 12 37.722  -20 41 34.10        21LW43    266  C~8ebm      
2022 10  20.29842  19 12 37.793  -20 41 33.83        21LW43    266  C~8ebm      
2022 10  21.20926  19 12 39.581  -20 41 27.66        21LW43    266  C~8ebm      
2022 10  21.25420  19 12 39.668  -20 41 27.34        21LW43    266  C~8ebm      
2022 10  21.29846  19 12 39.754  -20 41 27.02        21LW43    266  C~8ebm      

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    -0.00       0.00     0.06
     2   0.0002     -4.98     0.00       0.54     0.06
     3   0.0005    -10.22     0.01       1.13     0.06
     4   0.0219   -485.10    -0.02      50.63    -0.04
     5   0.0221   -489.24    -0.02      51.05    -0.02
     6   0.0223   -494.32    -0.03      51.57    -0.02
     7   0.0709  -1671.28     0.02     159.62    -0.06
     8   0.0712  -1677.42     0.03     160.15    -0.06
     9   0.0714  -1683.38     0.02     160.67    -0.06
    10   0.2431  -5171.63    -0.05     483.71     0.03
    11   0.2433  -5174.03    -0.00     484.08     0.03
    12   0.2435  -5176.44     0.03     484.46     0.03
    13   1.3628   -566.89    -0.00    2731.84    -0.01
    14   1.3630   -565.74    -0.01    2732.00    -0.01
    15   1.3631   -564.72     0.01    2732.14    -0.01
    16   1.3656   -539.06    -0.00    2735.15     0.01
    17   1.3657   -537.81     0.00    2735.32     0.01
    18   1.3658   -536.57    -0.00    2735.49     0.01

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.

21LW43    quality flag:2

Type:       SCATNEAR     3:1II  SCATNEAR

axisobj        61.935    62.239    61.825
ecceobj         0.295     0.298     0.296
incobj         24.075    24.091    24.061
qmin           42.150    43.354    42.229
qmax           83.417    82.981    83.064
amean          62.334    62.630    62.194
amin           61.650    62.006    61.541
amax           63.184    63.402    63.005
emean           0.305     0.214     0.303
emin            0.289     0.162     0.290
emax            0.322     0.309     0.319
imean          25.341    28.187    25.404
imin           24.895    25.552    25.021
imax           25.826    29.359    25.836
excite_mean     0.525     0.520     0.525
fracstop        1.000     1.000     1.000
cjmean          2.959     2.961     2.957

libcent 0      -180.0     198.6    -180.0
libamp  0      -180.0     103.1    -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       168.2     149.3     179.4
kozaiamp        179.9     180.0     180.0