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: 18FY73
# Created Sat May 10 01:11:10 2025
# Orbit generated by ELGB
# -->Covariance matrix from a Bernstein fit
# Fitting 21 observations of 24
# Arc: 2.97y
# First observation: 2016/03/17
# Last observation: 2019/03/08
# Chi-squared of fit: 7.90 DOF: 36 RMS: 0.11
# Min/Max residuals: -0.27 0.22
# Exact a, adot, b, bdot, g, gdot:
1.763097E-05 3.366918E-02 1.188240E-06 2.401698E-03 2.935477E-02 3.697200E-04
# Covariance matrix:
6.8306E-13 -3.6502E-13 4.0501E-14 -2.5451E-14 7.2470E-14 -1.0057E-12
-3.6502E-13 2.2218E-13 -2.5617E-14 1.6103E-14 -3.2820E-14 6.3591E-13
4.0501E-14 -2.5617E-14 1.5842E-13 -3.2702E-14 6.6720E-15 -7.7271E-14
-2.5451E-14 1.6103E-14 -3.2702E-14 1.1240E-14 -4.0170E-15 4.8542E-14
7.2470E-14 -3.2820E-14 6.6720E-15 -4.0170E-15 4.0535E-13 -1.7091E-13
-1.0057E-12 6.3591E-13 -7.7271E-14 4.8542E-14 -1.7091E-13 1.9192E-12
# lat0 lon0 xBary yBary zBary JD0
0.299014 170.429019 -0.111906 0.005287 -0.985178 2457464.925037
# Heliocentric elements and errors
Epoch: 2457464.5000 = 2016/03/17
Mean Anomaly: 3.55771 +/- 0.010
Argument of Peri: 358.88412 +/- 0.014
Long of Asc Node: 166.53967 +/- 0.000
Inclination: 4.08115 +/- 0.000
Eccentricity: 0.17990838 +/- 0.0001
Semi-Major Axis: 42.71809637 +/- 0.0053
Time of Perihelion: 2456456.6759 +/- 2.7
Perihelion: 35.03275293 +/- 0.0058
Aphelion: 50.40343982 +/- 0.0073
Period (y) 279.2068 +/- 0.05
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X -34.58532858 +/- 0.0007
Ecliptic Y 5.71498998 +/- 0.0001
Ecliptic Z 0.17783943 +/- 0.0000
Ecliptic XDOT -0.00055502 +/- 0.0000
Ecliptic YDOT -0.00309797 +/- 0.0000
Ecliptic ZDOT 0.00022419 +/- 0.0000
# Distances at JD0 (AU)
Heliocenter to KBO 35.05477272 +/- 0.0007
Geocenter to KBO 34.06605241 +/- 0.0007
# Hcoef: 7.61
The following table shows the complete astrometric record for 18FY73. 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 (18FY73) followed by the observatory code and reference code for the source of the astrometry.
2016 03 17.424248 11 25 17.70 +04 04 01.7 18FY73 T09 C~89VN 2016 03 17.566829 11 25 16.93 +04 04 06.6 18FY73 T09 C~89VN 2018 03 10.454806 11 40 35.66 +02 43 15.6 18FY73 T09 C~89VN 2018 03 18.45971 11 39 53.98 +02 47 57.0 23.2i 18FY73 T09 C~89VN 2018 03 18.48956 11 39 53.82 +02 47 58.2 23.0i 18FY73 T09 C~89VN 2018 03 18.50304 11 39 53.75 +02 47 58.5 22.8i 18FY73 T09 C~89VN 2018 03 18.56001 11 39 53.45 +02 48 00.4 22.6i 18FY73 T09 C~89VN 2018 04 22.298971 11 37 10.17 +03 06 12.7 18FY73 T09 C~89VN 2018 04 22.407617 11 37 09.74 +03 06 15.6 18FY73 T09 C~89VN 2018 04 24.35200 11 37 02.43 +03 07 04.4 23.0z 18FY73 T09 C~89VN 2018 04 24.39881 11 37 02.24 +03 07 05.4 22.9z 18FY73 T09 C~89VN 2018 04 24.42918 11 37 02.13 +03 07 06.2 22.4z 18FY73 T09 C~89VN 2018 04 24.44256 11 37 02.09 +03 07 06.2 22.7z 18FY73 T09 C~89VN 2018 04 24.48536 11 37 01.93 +03 07 07.6 22.4z 18FY73 T09 C~89VN 2019 02 05.457878 11 50 23.90 +01 47 27.7 18FY73 T09 C~89VN 2019 02 05.498105 11 50 23.75 +01 47 28.8 18FY73 T09 C~89VN 2019 03 02.51613 11 48 34.35 +02 00 11.5 23.0y 18FY73 T09 C~8CPH 2019 03 02.55921 11 48 34.13 +02 00 12.8 22.9y 18FY73 T09 C~8CPH 2019 03 02.60017 11 48 33.93 +02 00 14.5 22.5y 18FY73 T09 C~8CPH 2019 03 08.391723 11 48 04.73 +02 03 34.2 18FY73 T09 C~89VN 2019 03 08.433927 11 48 04.51 +02 03 35.7 18FY73 T09 C~89VN 2025 04 23.25951 12 27 22.853 -01 19 10.88 23.3G 18FY73 G37 2025 04 23.29705 12 27 22.653 -01 19 09.81 18FY73 G37 2025 04 23.33554 12 27 22.510 -01 19 08.87 18FY73 G37
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 0.10 0.00 -0.02
2 0.0004 0.00 -0.15 0.00 -0.05
3 1.9795 0.00 0.03 0.00 0.13
4 2.0015 0.00 0.01 0.00 0.07
5 2.0015 0.00 -0.02 0.00 0.22
6 2.0016 0.00 0.00 0.00 0.05
7 2.0017 0.00 0.02 0.00 -0.04
8 2.0969 0.00 0.19 0.00 -0.17
9 2.0971 0.00 0.14 0.00 -0.04
10 2.1025 0.00 -0.01 0.00 0.15
11 2.1026 0.00 -0.21 0.00 0.00
12 2.1027 0.00 -0.14 0.00 0.06
13 2.1027 0.00 0.01 0.00 -0.27
14 2.1028 0.00 0.02 0.00 0.09
15 2.8885 0.00 0.08 0.00 -0.07
16 2.8886 0.00 0.05 0.00 -0.00
17 2.9571 0.00 -0.12 0.00 -0.01
18 2.9572 0.00 -0.15 0.00 -0.18
19 2.9574 0.00 -0.05 0.00 0.13
20 2.9732 0.00 0.06 0.00 -0.03
21 2.9733 0.00 0.06 0.00 0.00
22 9.1002 0.00 ( -2.67) 0.00 ( 1.09)
23 9.1003 0.00 ( -3.07) 0.00 ( 1.06)
24 9.1004 0.00 ( -2.56) 0.00 ( 0.87)
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.
18FY73 quality flag:3 Type: 5:3EE 5:3EE 5:3EE axisobj 42.325 42.325 42.325 ecceobj 0.172 0.172 0.172 incobj 4.098 4.098 4.098 qmin 34.354 34.356 34.353 qmax 50.858 50.884 50.894 amean 42.328 42.328 42.328 amin 41.893 41.893 41.889 amax 42.818 42.811 42.819 emean 0.172 0.172 0.172 emin 0.155 0.155 0.155 emax 0.189 0.189 0.189 imean 3.908 3.910 3.910 imin 3.277 3.279 3.283 imax 4.811 4.810 4.822 excite_mean 0.185 0.185 0.185 fracstop 1.000 1.000 1.000 cjmean 3.042 3.042 3.042 libcent 0 180.8 181.3 181.2 libamp 0 82.3 81.8 81.8 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 158.4 158.2 158.7 kozaiamp 180.0 180.0 179.9