Orbit Fit and Astrometric record for 21RK237

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: 21RK237   
# Created Tue Apr  1 01:11:26 2025
# Orbit generated from Bernstein formalism
# Fitting      8 observations of      8
# Arc:   2.11y
# First observation: 2019/08/29
#  Last observation: 2021/10/07
Preliminary a, adot, b, bdot, g, gdot:
   0.000009   0.024090  -0.000001   0.001516   0.024561   0.000000
# Chi-squared of fit:    11.18 DOF:     10 RMS:  0.21
# Min/Max residuals:    -0.46    0.44
# Exact a, adot, b, bdot, g, gdot:
  1.527860E-05  2.412623E-02  1.317241E-06  1.520215E-03  2.453530E-02  1.233266E-03
# Covariance matrix:
  7.2622E-13 -1.7436E-12  1.6026E-14 -9.3268E-14 -1.2619E-12 -2.8759E-11
 -1.7436E-12  5.7324E-11 -6.4197E-13  3.6317E-12  6.3061E-11  1.1199E-09
  1.6026E-14 -6.4197E-13  6.3126E-13 -3.7555E-13 -7.0858E-13 -1.2600E-11
 -9.3268E-14  3.6317E-12 -3.7555E-13  4.8607E-13  3.9971E-12  7.1324E-11
 -1.2619E-12  6.3061E-11 -7.0858E-13  3.9971E-12  7.0971E-11  1.2326E-09
 -2.8759E-11  1.1199E-09 -1.2600E-11  7.1324E-11  1.2326E-09  2.1994E-08
#      lat0       lon0       xBary       yBary       zBary        JD0
   -1.973789   -9.322608    0.260363   -0.033409   -0.969578  2458724.712719
# Heliocentric elements and errors
Epoch:              2458720.5000  =  2019/08/25
Mean Anomaly:           54.44483 +/-     2.743
Argument of Peri:      271.76989 +/-     3.452
Long of Asc Node:       18.52041 +/-     0.008
Inclination:             4.07257 +/-     0.001
Eccentricity:         0.05665563 +/-    0.0053
Semi-Major Axis:     43.05378012 +/-    0.0095
Time of Perihelion: 2443115.2953 +/-     786.2
Perihelion:          40.61454105 +/-    0.2270
Aphelion:            45.49301920 +/-    0.2271
Period (y)              282.5043 +/-      0.09
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X           41.11341952 +/-    0.0138
Ecliptic Y           -7.01960658 +/-    0.0023
Ecliptic Z           -1.40373165 +/-    0.0005
Ecliptic XDOT         0.00058607 +/-    0.0000
Ecliptic YDOT         0.00263399 +/-    0.0000
Ecliptic ZDOT         0.00016457 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   41.73198538 +/-    0.0136
Geocenter to KBO     40.75760343 +/-    0.0140
# Hcoef:  9.33

The following table shows the complete astrometric record for 21RK237. 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 (21RK237) followed by the observatory code and reference code for the source of the astrometry.

2019 08  29.211918 23 28 51.506  -05 30 31.79  25.2r 21RK237   W84  C~7XPn      
2019 08  29.387113 23 28 50.732  -05 30 36.56  25.2r 21RK237   W84  C~7XPn      
2020 10  16.001792 23 30 20.169  -05 14 13.41  25.5r 21RK237   W84  C~7XPn      
2020 10  16.175804 23 30 19.514  -05 14 16.94  25.5r 21RK237   W84  C~7XPn      
2021 09  05.096099 23 38 14.476  -04 18 39.04  25.7r 21RK237   W84  C~7XPn      
2021 09  05.195929 23 38 13.994  -04 18 42.80  25.7r 21RK237   W84  C~7XPn      
2021 10  07.004805 23 35 53.714  -04 33 07.14  25.4r 21RK237   W84  C~7XPn      
2021 10  07.169933 23 35 53.006  -04 33 11.12  25.4r 21RK237   W84  C~7XPn      

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     0.06       0.00    -0.07
     2   0.0005    -12.50    -0.05       0.17     0.00
     3   1.1329   1602.77    -0.09     376.46     0.01
     4   1.1334   1592.38     0.07     377.08     0.14
     5   2.0202   9440.09     0.44     628.71     0.28
     6   2.0205   9431.96    -0.46     628.12    -0.39
     7   2.1076   7159.63     0.06     668.05    -0.07
     8   2.1080   7148.32    -0.03     668.60     0.09

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.

21RK237    quality flag:3

Type:      CLASSICAL CLASSICAL CLASSICAL

axisobj        43.070    43.126    43.027
ecceobj         0.054     0.066     0.044
incobj          4.067     4.066     4.068
qmin           40.114    39.651    40.449
qmax           46.014    46.573    45.540
amean          42.973    43.031    42.929
amin           42.640    42.698    42.598
amax           43.310    43.376    43.271
emean           0.044     0.056     0.035
emin            0.023     0.035     0.013
emax            0.063     0.074     0.053
imean           3.544     3.550     3.538
imin            2.557     2.539     2.560
imax            4.486     4.499     4.476
excite_mean     0.076     0.083     0.071
fracstop        1.000     1.000     1.000
cjmean          3.082     3.082     3.083

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       189.4     190.0     189.8
kozaiamp        180.0     179.9     179.9