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: 21DK18
# Created Mon Apr 28 01:11:25 2025
# Orbit generated from Bernstein formalism
# Fitting 18 observations of 18
# Arc: 4.03y
# First observation: 2020/02/26
# Last observation: 2024/03/08
Preliminary a, adot, b, bdot, g, gdot:
-0.000335 0.012826 0.000099 -0.003365 0.015040 0.000000
# Chi-squared of fit: 5.17 DOF: 30 RMS: 0.09
# Min/Max residuals: -0.22 0.19
# Exact a, adot, b, bdot, g, gdot:
1.339527E-05 1.237406E-02 -2.725045E-06 -3.240447E-03 1.493296E-02 -9.227189E-03
# Covariance matrix:
5.5123E-13 -5.0468E-13 -7.8493E-14 1.0560E-13 -1.6623E-13 -7.4554E-12
-5.0468E-13 6.2310E-13 1.1195E-13 -1.5116E-13 1.8921E-13 1.0664E-11
-7.8493E-14 1.1195E-13 2.9845E-13 -1.4811E-13 3.8967E-14 2.1593E-12
1.0560E-13 -1.5116E-13 -1.4811E-13 1.1166E-13 -4.9573E-14 -2.9168E-12
-1.6623E-13 1.8921E-13 3.8967E-14 -4.9573E-14 3.3079E-13 3.5426E-12
-7.4554E-12 1.0664E-11 2.1593E-12 -2.9168E-12 3.5426E-12 2.0575E-10
# lat0 lon0 xBary yBary zBary JD0
4.871702 124.039590 -0.533701 0.071503 -0.838830 2458905.627206
# Heliocentric elements and errors
Epoch: 2458900.5000 = 2020/02/21
Mean Anomaly: 358.96263 +/- 0.034
Argument of Peri: 235.25905 +/- 0.029
Long of Asc Node: 322.19596 +/- 0.001
Inclination: 15.47338 +/- 0.001
Eccentricity: 0.94083443 +/- 0.0013
Semi-Major Axis: 747.41266735 +/- 16.4549
Time of Perihelion: 2480407.0222 +/- 10.4
Perihelion: 44.22109504 +/- 1.3993
Aphelion: 1450.60423966 +/- 31.9521
Period (y) 20433.7880 +/- 674.80
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X -38.25980707 +/- 0.0015
Ecliptic Y 55.68200082 +/- 0.0021
Ecliptic Z 5.68684614 +/- 0.0002
Ecliptic XDOT -0.00095641 +/- 0.0000
Ecliptic YDOT -0.00262241 +/- 0.0000
Ecliptic ZDOT -0.00073587 +/- 0.0000
# Distances at JD0 (AU)
Heliocenter to KBO 67.79851231 +/- 0.0019
Geocenter to KBO 66.96595215 +/- 0.0026
# Hcoef: 6.69
The following table shows the complete astrometric record for 21DK18. 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 (21DK18) followed by the observatory code and reference code for the source of the astrometry.
2020 02 26.126405 08 30 28.59 +23 58 31.5 24.5V 21DK18 W84 C~5rBm 2020 02 26.128468 08 30 28.60 +23 58 31.8 21DK18 W84 C~5rBm 2021 02 17.25324 08 33 41.803 +23 36 13.90 24.6r 21DK18 568 C~5oWe 2021 02 17.42570 08 33 41.264 +23 36 15.15 24.6r 21DK18 568 C~5oWe 2021 03 09.06636 08 32 47.221 +23 37 58.38 24.8G 21DK18 304 C~5oWe 2021 03 09.11920 08 32 47.096 +23 37 58.77 24.6G 21DK18 304 C~5oWe 2021 03 17.12379 08 32 29.682 +23 38 17.80 24.8r 21DK18 304 C~5oWe 2021 03 18.08040 08 32 27.824 +23 38 19.02 24.7r 21DK18 304 C~5oWe 2021 12 02.30868 08 40 17.453 +23 01 37.40 24.8r 21DK18 304 C~5oWe 2021 12 06.29584 08 40 10.633 +23 02 08.57 24.9r 21DK18 304 C~5oWe 2021 12 07.30601 08 40 08.763 +23 02 17.17 24.7r 21DK18 304 C~5oWe 2022 03 07.03706 08 35 43.775 +23 15 52.22 25.2G 21DK18 304 C~5oWe 2022 03 07.04747 08 35 43.731 +23 15 52.23 25.1G 21DK18 304 C~5oWe 2022 03 07.12631 08 35 43.531 +23 15 52.81 25.2G 21DK18 304 C~5oWe 2022 03 07.13663 08 35 43.516 +23 15 52.87 25.1G 21DK18 304 C~5oWe 2022 04 09.02361 08 34 48.790 +23 16 05.74 24.8r 21DK18 304 C~5oWe 2024 03 07.05906 08 41 31.929 +22 30 05.22 24.9r 21DK18 304 C~7um0 2024 03 08.05293 08 41 29.398 +22 30 09.83 25.0r 21DK18 304 C~7um0
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 -0.15
2 0.0000 0.06 0.08 0.32 0.19
3 0.9778 2899.98 0.02 -642.84 -0.02
4 0.9782 2892.49 0.03 -643.47 -0.00
5 1.0320 2147.28 -0.07 -727.97 -0.12
6 1.0322 2145.52 -0.08 -728.01 0.10
7 1.0541 1908.92 -0.02 -768.77 0.05
8 1.0567 1883.88 0.11 -773.90 -0.03
9 1.7664 8704.27 0.12 -1263.23 0.14
10 1.7773 8605.08 0.00 -1257.60 -0.10
11 1.7801 8577.87 -0.13 -1256.00 0.13
12 2.0258 4832.22 0.14 -1404.54 -0.12
13 2.0258 4831.63 -0.08 -1404.68 -0.22
14 2.0260 4828.81 -0.12 -1404.81 0.03
15 2.0260 4828.60 0.03 -1404.81 0.09
16 2.1161 4095.17 0.02 -1582.24 -0.05
17 4.0272 10196.37 0.01 -2822.84 0.10
18 4.0299 10161.23 0.00 -2827.58 -0.04
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.
21DK18 quality flag:1 Type: SCATNEAR SCATNEAR SCATNEAR axisobj 759.339 810.804 714.199 ecceobj 0.941 0.945 0.937 incobj 15.440 15.440 15.441 qmin 36.957 36.569 37.384 qmax 1829.075 2045.828 1777.582 amean 762.778 818.541 734.521 amin 692.104 711.976 671.118 amax 936.748 1045.075 911.039 emean 0.942 0.946 0.939 emin 0.929 0.933 0.928 emax 0.953 0.958 0.951 imean 16.731 16.742 16.729 imin 16.005 15.977 16.052 imax 17.587 17.693 17.529 excite_mean 0.985 0.989 0.982 fracstop 1.000 1.000 1.000 cjmean 3.283 3.280 3.286 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 237.2 236.9 237.1 kozaiamp 6.6 6.7 6.6