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: 18AX18 # Created Tue Apr 1 01:11:08 2025 # Orbit generated from Bernstein formalism # Fitting 10 observations of 10 # Arc: 1.87y # First observation: 2018/01/15 # Last observation: 2019/11/30 Preliminary a, adot, b, bdot, g, gdot: -0.000001 0.011183 0.000003 -0.002311 0.016162 0.000000 # Chi-squared of fit: 7.15 DOF: 14 RMS: 0.15 # Min/Max residuals: -0.35 0.28 # Exact a, adot, b, bdot, g, gdot: 1.088220E-05 1.103028E-02 -1.012278E-06 -2.288030E-03 1.620030E-02 -2.583552E-03 # Covariance matrix: 7.2647E-13 -1.4592E-12 -4.0590E-14 1.6772E-13 -2.9588E-14 -3.2231E-11 -1.4592E-12 1.1182E-10 1.2893E-12 -1.4256E-11 -8.1950E-11 2.2941E-09 -4.0590E-14 1.2893E-12 5.0811E-13 -5.4710E-13 -8.4613E-13 2.7789E-11 1.6772E-13 -1.4256E-11 -5.4710E-13 2.2443E-12 1.0380E-11 -2.9487E-10 -2.9588E-14 -8.1950E-11 -8.4613E-13 1.0380E-11 6.3289E-11 -1.6513E-09 -3.2231E-11 2.2941E-09 2.7789E-11 -2.9487E-10 -1.6513E-09 4.7682E-08 # lat0 lon0 xBary yBary zBary JD0 -17.344312 78.735255 -0.580816 -0.238355 -0.763719 2458133.918631 # Heliocentric elements and errors Epoch: 2458130.5000 = 2018/01/12 Mean Anomaly: 239.24541 +/- 2.242 Argument of Peri: 21.25383 +/- 2.042 Long of Asc Node: 204.07258 +/- 0.009 Inclination: 20.56465 +/- 0.002 Eccentricity: 0.29173613 +/- 0.0103 Semi-Major Axis: 52.12231375 +/- 0.1660 Time of Perihelion: 2504234.1297 +/- 827.3 Perihelion: 36.91635153 +/- 0.5479 Aphelion: 67.32827596 +/- 0.5765 Period (y) 376.3082 +/- 1.80 # Ecliptic coordinates at JD0 (AU and AU/d) Ecliptic X 11.09397651 +/- 0.0057 Ecliptic Y 58.67744565 +/- 0.0284 Ecliptic Z -18.40180551 +/- 0.0090 Ecliptic XDOT -0.00192618 +/- 0.0000 Ecliptic YDOT -0.00016257 +/- 0.0000 Ecliptic ZDOT -0.00023908 +/- 0.0000 # Distances at JD0 (AU) Heliocenter to KBO 62.48796195 +/- 0.0268 Geocenter to KBO 61.72724655 +/- 0.0303 # Hcoef: 6.50
The following table shows the complete astrometric record for 18AX18. 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 (18AX18) followed by the observatory code and reference code for the source of the astrometry.
2018 01 15.41783 05 16 48.039 +05 40 25.16 24.4r 18AX18 568 C~2yg3 2018 01 16.41334 05 16 45.281 +05 40 31.23 24.5r 18AX18 568 C~2yg3 2018 12 04.14405 05 21 43.188 +05 35 59.28 24.2r 18AX18 304 C~2yg3 2018 12 04.25870 05 21 42.767 +05 35 58.56 18AX18 304 C~2yg3 2018 12 04.26384 05 21 42.779 +05 35 58.68 24.3r 18AX18 304 C~2yg3 2018 12 04.26873 05 21 42.774 +05 35 58.53 18AX18 304 C~2yg3 2018 12 09.18298 05 21 25.716 +05 35 26.42 24.3r 18AX18 304 C~2yg3 2018 12 09.21921 05 21 25.582 +05 35 26.51 18AX18 304 C~2yg3 2019 11 29.28837 05 24 36.193 +05 31 37.33 24.5r 18AX18 304 C~3d0D 2019 11 30.26850 05 24 32.889 +05 31 28.82 24.3r 18AX18 304 C~3d0D
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 -0.02 0.00 -0.25
2 0.0027 -40.57 -0.02 9.27 -0.01
3 0.8836 4372.92 -0.06 -604.57 -0.04
4 0.8839 4366.60 -0.35 -604.81 0.09
5 0.8839 4366.78 0.11 -604.71 0.22
6 0.8839 4366.70 0.28 -604.85 0.09
7 0.8974 4110.23 0.08 -617.50 -0.08
8 0.8975 4108.25 0.02 -617.25 0.22
9 1.8696 6930.68 -0.04 -1060.79 -0.06
10 1.8723 6880.79 0.01 -1065.59 -0.18
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.
18AX18 quality flag:2 Type: SCATNEAR 7:3EEEE SCATNEAR axisobj 52.548 53.100 52.205 ecceobj 0.281 0.313 0.254 incobj 20.452 20.447 20.457 qmin 35.811 35.209 37.130 qmax 69.481 71.747 67.586 amean 52.229 52.969 51.999 amin 51.697 52.292 51.518 amax 52.952 53.757 52.612 emean 0.295 0.320 0.268 emin 0.276 0.304 0.252 emax 0.315 0.335 0.285 imean 20.351 20.876 20.491 imin 19.562 20.393 19.938 imax 20.980 21.298 20.991 excite_mean 0.456 0.479 0.441 fracstop 1.000 1.000 1.000 cjmean 2.936 2.916 2.951 libcent 0 -180.0 179.0 -180.0 libamp 0 -180.0 146.8 -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 164.7 155.5 168.8 kozaiamp 180.0 180.0 180.0