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: 17QU218 # Created Mon Jul 7 01:11:33 2025 # Orbit generated from Bernstein formalism # Fitting 41 observations of 41 # Arc: 3.86y # First observation: 2013/10/10 # Last observation: 2017/08/19 Preliminary a, adot, b, bdot, g, gdot: 0.001463 0.025960 0.000363 0.015372 0.025532 0.000000 # Chi-squared of fit: 10.30 DOF: 76 RMS: 0.09 # Min/Max residuals: -0.28 0.18 # Exact a, adot, b, bdot, g, gdot: 1.518317E-05 2.609316E-02 9.310620E-06 1.554406E-02 2.688914E-02 3.196575E-03 # Covariance matrix: 1.1780E-12 -7.0753E-13 3.2922E-13 -2.9771E-13 -3.0876E-13 -3.8326E-12 -7.0753E-13 6.4547E-13 -2.9857E-13 2.8207E-13 3.7062E-14 3.6657E-12 3.2922E-13 -2.9857E-13 5.8197E-13 -2.8629E-13 -7.5545E-14 -1.9070E-12 -2.9771E-13 2.8207E-13 -2.8629E-13 1.8729E-13 5.4199E-14 1.7807E-12 -3.0876E-13 3.7062E-14 -7.5545E-14 5.4199E-14 3.5467E-13 6.5754E-13 -3.8326E-12 3.6657E-12 -1.9070E-12 1.7807E-12 6.5754E-13 2.3085E-11 # lat0 lon0 xBary yBary zBary JD0 11.583825 -30.704372 -0.733824 0.136049 -0.663198 2456575.582875 # Heliocentric elements and errors Epoch: 2456570.5000 = 2013/10/05 Mean Anomaly: 19.52690 +/- 0.017 Argument of Peri: 347.80021 +/- 0.031 Long of Asc Node: 312.05323 +/- 0.000 Inclination: 32.54466 +/- 0.000 Eccentricity: 0.26083388 +/- 0.0002 Semi-Major Axis: 49.43644309 +/- 0.0087 Time of Perihelion: 2449683.9747 +/- 5.6 Perihelion: 36.54174406 +/- 0.0104 Aphelion: 62.33114211 +/- 0.0137 Period (y) 347.5994 +/- 0.09 # Ecliptic coordinates at JD0 (AU and AU/d) Ecliptic X 32.28148105 +/- 0.0007 Ecliptic Y -18.31439769 +/- 0.0004 Ecliptic Z 7.46806180 +/- 0.0002 Ecliptic XDOT 0.00135131 +/- 0.0000 Ecliptic YDOT 0.00228241 +/- 0.0000 Ecliptic ZDOT 0.00161595 +/- 0.0000 # Distances at JD0 (AU) Heliocenter to KBO 37.85872593 +/- 0.0006 Geocenter to KBO 37.18972883 +/- 0.0008 # Hcoef: 8.07
The following table shows the complete astrometric record for 17QU218. 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 (17QU218) followed by the observatory code and reference code for the source of the astrometry.
2013 10 10.082097 21 49 34.462 -00 50 40.42 23.4r 17QU218 W84 C~8vJE 2015 08 09.49543 22 03 03.60 +02 13 20.1 23.4y 17QU218 T09 C~8vJE 2015 08 09.50353 22 03 03.56 +02 13 20.1 23.4y 17QU218 T09 C~8vJE 2015 08 09.51171 22 03 03.52 +02 13 20.1 23.7y 17QU218 T09 C~8vJE 2015 08 11.47147 22 02 53.58 +02 12 53.1 23.9i 17QU218 T09 C~8vJE 2015 08 11.47955 22 02 53.54 +02 12 53.1 23.9i 17QU218 T09 C~8vJE 2015 08 11.48763 22 02 53.49 +02 12 53.1 24.2i 17QU218 T09 C~8vJE 2015 08 11.49573 22 02 53.45 +02 12 52.8 23.9i 17QU218 T09 C~8vJE 2015 08 20.33669 22 02 07.87 +02 10 29.5 23.6z 17QU218 T09 C~8vJE 2015 08 20.38668 22 02 07.59 +02 10 28.5 23.6z 17QU218 T09 C~8vJE 2015 08 20.39479 22 02 07.55 +02 10 28.5 23.6z 17QU218 T09 C~8vJE 2016 06 04.53651 22 10 51.72 +03 24 45.8 23.5z 17QU218 T09 C~8vJE 2016 06 04.57160 22 10 51.68 +03 24 46.7 23.8z 17QU218 T09 C~8vJE 2016 07 05.42198 22 09 50.41 +03 34 23.7 24.2i 17QU218 T09 C~8vJE 2016 07 05.45137 22 09 50.32 +03 34 24.0 23.8i 17QU218 T09 C~8vJE 2016 07 05.46493 22 09 50.27 +03 34 24.0 23.7i 17QU218 T09 C~8vJE 2016 07 07.43034 22 09 43.70 +03 34 39.9 24.8g 17QU218 T09 C~8vJE 2016 07 07.44100 22 09 43.66 +03 34 39.7 24.5g 17QU218 T09 C~8vJE 2016 07 07.44313 22 09 43.65 +03 34 39.9 24.7g 17QU218 T09 C~8vJE 2016 07 07.45369 22 09 43.61 +03 34 39.9 24.8g 17QU218 T09 C~8vJE 2016 07 09.43185 22 09 36.72 +03 34 53.3 23.3y 17QU218 T09 C~8vJE 2016 07 09.43996 22 09 36.70 +03 34 53.3 23.6y 17QU218 T09 C~8vJE 2016 07 09.44538 22 09 36.68 +03 34 53.3 22.8y 17QU218 T09 C~8vJE 2016 08 06.39996 22 07 35.23 +03 33 33.9 23.9r 17QU218 T09 C~8vJE 2016 08 06.40707 22 07 35.19 +03 33 33.8 24.1r 17QU218 T09 C~8vJE 2016 08 06.40918 22 07 35.18 +03 33 33.6 24.0r 17QU218 T09 C~8vJE 2016 08 28.31665 22 05 43.12 +03 27 29.9 23.5i 17QU218 T09 C~8vJE 2016 08 28.32210 22 05 43.10 +03 27 29.6 23.6i 17QU218 T09 C~8vJE 2017 06 20.48411 22 14 45.42 +04 48 47.6 23.7z 17QU218 T09 C~8vJE 2017 06 20.51243 22 14 45.38 +04 48 48.3 23.4z 17QU218 T09 C~8vJE 2017 06 20.52313 22 14 45.36 +04 48 48.6 23.7z 17QU218 T09 C~8vJE 2017 06 24.46869 22 14 37.06 +04 50 03.8 23.5i 17QU218 T09 C~8vJE 2017 06 24.48739 22 14 37.02 +04 50 04.2 23.8i 17QU218 T09 C~8vJE 2017 06 24.49273 22 14 37.01 +04 50 04.3 23.8i 17QU218 T09 C~8vJE 2017 07 19.42071 22 13 16.40 +04 53 58.6 23.2y 17QU218 T09 C~8vJE 2017 07 19.44952 22 13 16.27 +04 53 58.8 23.4y 17QU218 T09 C~8vJE 2017 08 18.32705 22 10 55.06 +04 49 53.4 24.4g 17QU218 T09 C~8vJE 2017 08 18.35014 22 10 54.94 +04 49 53.1 24.4g 17QU218 T09 C~8vJE 2017 08 19.34646 22 10 49.83 +04 49 36.4 24.0r 17QU218 T09 C~8vJE 2017 08 19.36971 22 10 49.70 +04 49 35.9 23.9r 17QU218 T09 C~8vJE 2017 08 19.38020 22 10 49.65 +04 49 35.7 24.0r 17QU218 T09 C~8vJE
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 0.03 0.00 -0.04
2 1.8300 15210.73 -0.13 6238.41 -0.08
3 1.8300 15210.17 -0.07 6238.62 0.02
4 1.8301 15209.60 0.00 6238.82 0.11
5 1.8354 15059.50 0.01 6264.23 -0.12
6 1.8354 15058.94 0.08 6264.44 -0.02
7 1.8355 15058.23 0.00 6264.70 0.13
8 1.8355 15057.56 -0.03 6264.62 -0.05
9 1.8597 14362.76 0.13 6362.78 -0.02
10 1.8598 14358.45 -0.13 6363.27 -0.02
11 1.8599 14357.88 -0.04 6363.47 0.10
12 2.6515 23343.38 0.11 7899.72 0.08
13 2.6516 23343.12 -0.16 7900.77 0.07
14 2.7360 22669.78 0.03 8760.54 -0.03
15 2.7361 22668.60 0.15 8761.28 -0.03
16 2.7362 22667.89 0.05 8761.54 -0.12
17 2.7415 22579.78 0.06 8810.11 0.08
18 2.7416 22579.14 -0.08 8810.13 -0.17
19 2.7416 22579.07 -0.05 8810.37 0.01
20 2.7416 22578.50 -0.12 8810.57 -0.04
21 2.7470 22484.98 -0.03 8858.40 0.13
22 2.7470 22484.70 0.09 8858.51 0.04
23 2.7471 22484.41 0.07 8858.61 0.01
24 2.8236 20728.13 0.08 9402.49 0.09
25 2.8236 20727.53 0.02 9402.60 0.09
26 2.8236 20727.32 -0.04 9402.46 -0.08
27 2.8836 19008.88 -0.01 9629.38 0.09
28 2.8836 19008.49 0.04 9629.20 -0.12
29 3.6945 28438.26 -0.20 11506.89 -0.07
30 3.6945 28437.93 0.08 11507.76 -0.04
31 3.6946 28437.75 0.13 11508.14 0.03
32 3.7054 28345.03 -0.09 11621.96 -0.09
33 3.7054 28344.60 -0.01 11622.54 -0.04
34 3.7054 28344.49 0.03 11622.69 -0.05
35 3.7737 27271.70 0.02 12254.67 -0.28
36 3.7738 27269.90 -0.07 12255.52 -0.07
37 3.8556 25165.72 -0.04 12737.35 0.02
38 3.8556 25163.90 -0.01 12737.67 0.10
39 3.8584 25085.13 0.11 12747.67 0.18
40 3.8584 25083.10 -0.05 12747.86 0.13
41 3.8584 25082.31 0.01 12747.92 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.
17QU218 quality flag:3 Type: SCATNEAR SCATNEAR SCATNEAR axisobj 49.666 49.694 49.639 ecceobj 0.264 0.265 0.264 incobj 32.488 32.488 32.488 qmin 34.963 34.988 34.996 qmax 64.774 64.906 64.751 amean 49.619 49.640 49.541 amin 49.168 49.190 49.053 amax 50.179 50.208 50.128 emean 0.274 0.275 0.272 emin 0.255 0.256 0.254 emax 0.293 0.293 0.293 imean 33.621 33.626 33.664 imin 33.191 33.186 33.184 imax 34.162 34.150 34.153 excite_mean 0.618 0.618 0.617 fracstop 1.000 1.000 1.000 cjmean 2.662 2.662 2.662 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 154.6 154.8 157.3 kozaiamp 180.0 180.0 180.0