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: 18GT12 # Created Wed May 8 01:18:14 2024 # Orbit generated from Bernstein formalism # Fitting 8 observations of 8 # Arc: 0.81y # First observation: 2018/04/12 # Last observation: 2019/02/03 Preliminary a, adot, b, bdot, g, gdot: -0.000001 0.016381 -0.000007 0.004442 0.019009 0.000000 # Chi-squared of fit: 3.63 DOF: 10 RMS: 0.12 # Min/Max residuals: -0.16 0.27 # Exact a, adot, b, bdot, g, gdot: 1.366139E-05 1.595910E-02 3.080234E-06 4.390516E-03 1.900505E-02 -1.064173E-02 # Covariance matrix: 7.6035E-13 5.8482E-13 -6.5482E-14 6.1931E-13 2.7031E-12 1.5198E-10 5.8482E-13 3.1990E-09 -3.7711E-11 5.1948E-10 1.0401E-09 1.3417E-07 -6.5482E-14 -3.7711E-11 7.4164E-13 -6.6033E-12 -1.2539E-11 -1.5950E-09 6.1931E-13 5.1948E-10 -6.6033E-12 8.6531E-11 1.7129E-10 2.1906E-08 2.7031E-12 1.0401E-09 -1.2539E-11 1.7129E-10 3.5036E-10 4.4201E-08 1.5198E-10 1.3417E-07 -1.5950E-09 2.1906E-08 4.4201E-08 5.6560E-06 # lat0 lon0 xBary yBary zBary JD0 -2.834224 163.385520 -0.616628 -0.038741 -0.784798 2458220.547841 # Heliocentric elements and errors Epoch: 2458220.5000 = 2018/04/12 Mean Anomaly: 341.06243 +/- 10.008 Argument of Peri: 75.77878 +/- 0.913 Long of Asc Node: 174.15162 +/- 0.004 Inclination: 15.54809 +/- 0.006 Eccentricity: 0.65788248 +/- 0.1491 Semi-Major Axis: 98.20919064 +/- 33.9941 Time of Perihelion: 2476920.7931 +/- 1841.1 Perihelion: 33.59908430 +/- 18.6973 Aphelion: 162.81929698 +/- 58.2287 Period (y) 973.2769 +/- 505.33 # Ecliptic coordinates at JD0 (AU and AU/d) Ecliptic X -51.28979896 +/- 0.0496 Ecliptic Y 14.65307169 +/- 0.0148 Ecliptic Z -2.60159410 +/- 0.0025 Ecliptic XDOT 0.00078644 +/- 0.0003 Ecliptic YDOT -0.00263625 +/- 0.0001 Ecliptic ZDOT 0.00070737 +/- 0.0000 # Distances at JD0 (AU) Heliocenter to KBO 53.40528325 +/- 0.0478 Geocenter to KBO 52.61759076 +/- 0.0518 # Hcoef: 7.55
The following table shows the complete astrometric record for 18GT12. 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 (18GT12) followed by the observatory code and reference code for the source of the astrometry.
2018 04 12.04704 10 54 23.994 +03 54 44.67 24.8r 18GT12 807 C~31M1 2018 04 13.04733 10 54 21.395 +03 55 05.39 24.6r 18GT12 807 C~31M1 2018 05 14.22340 10 53 27.848 +04 03 27.47 18GT12 G37 C~31M1 2018 05 14.23067 10 53 27.855 +04 03 27.47 18GT12 G37 C~31M1 2018 05 15.25994 10 53 27.112 +04 03 38.36 18GT12 G37 C~31M1 2018 05 15.26719 10 53 27.115 +04 03 38.64 18GT12 G37 C~31M1 2019 02 02.27366 11 02 03.487 +03 20 20.61 24.7r 18GT12 304 C~31M1 2019 02 03.26880 11 02 00.514 +03 20 40.39 24.9r 18GT12 304 C~31M1
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 -0.08 0.00 0.12
2 0.0027 -43.86 0.08 4.29 -0.11
3 0.0881 -976.14 -0.15 162.29 -0.16
4 0.0881 -976.05 0.06 162.33 -0.15
5 0.0909 -990.48 0.02 168.15 0.03
6 0.0910 -990.54 0.06 168.43 0.27
7 0.8110 7147.44 -0.02 728.60 -0.13
8 0.8137 7098.68 0.02 729.76 0.13
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.
18GT12 quality flag:0 Type: ERR2LARGE ERR2LARGE ERR2LARGE axisobj 0.000 0.000 0.000 ecceobj -1.000 -1.000 -1.000 incobj -1.000 -1.000 -1.000 qmin 0.000 0.000 0.000 qmax 0.000 0.000 0.000 amean 0.000 0.000 0.000 amin 0.000 0.000 0.000 amax 0.000 0.000 0.000 emean 0.000 0.000 0.000 emin 0.000 0.000 0.000 emax 0.000 0.000 0.000 imean 0.000 0.000 0.000 imin 0.000 0.000 0.000 imax 0.000 0.000 0.000 excite_mean 0.000 0.000 0.000 fracstop 0.000 0.000 0.000 cjmean 0.000 0.000 0.000 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 0.0 0.0 0.0 kozaiamp 0.0 0.0 0.0