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 Thu Sep 4 01:11:37 2025 # Orbit generated by ELGB # -->Covariance matrix from a Bernstein fit # Fitting 44 observations of 44 # Arc: 11.80y # First observation: 2013/10/10 # Last observation: 2025/07/29 # Chi-squared of fit: 34.58 DOF: 82 RMS: 0.16 # Min/Max residuals: -0.61 0.21 # Exact a, adot, b, bdot, g, gdot: 1.515981E-05 2.609309E-02 9.327233E-06 1.554405E-02 2.688913E-02 3.196483E-03 # Covariance matrix: 6.1012E-13 -1.5968E-13 1.7553E-13 -8.0137E-14 -2.1537E-13 -3.8454E-13 -1.5968E-13 1.1448E-13 -1.2317E-13 5.9496E-14 -6.2593E-14 2.8014E-13 1.7553E-13 -1.2317E-13 2.3864E-13 -8.6452E-14 5.5989E-14 -3.1789E-13 -8.0137E-14 5.9496E-14 -8.6452E-14 3.8081E-14 -3.1220E-14 1.5324E-13 -2.1537E-13 -6.2593E-14 5.5989E-14 -3.1220E-14 3.0189E-13 -1.4053E-13 -3.8454E-13 2.8014E-13 -3.1789E-13 1.5324E-13 -1.4053E-13 7.2201E-13 # lat0 lon0 xBary yBary zBary JD0 11.583825 -30.704372 -0.733824 0.136049 -0.663198 2456575.582875 # Heliocentric elements and errors Epoch: 2456576.5000 = 2013/10/11 Mean Anomaly: 19.54406 +/- 0.006 Argument of Peri: 347.80038 +/- 0.007 Long of Asc Node: 312.05326 +/- 0.000 Inclination: 32.54470 +/- 0.000 Eccentricity: 0.26082816 +/- 0.0001 Semi-Major Axis: 49.43613073 +/- 0.0070 Time of Perihelion: 2449683.9897 +/- 2.5 Perihelion: 36.54179593 +/- 0.0069 Aphelion: 62.33046554 +/- 0.0100 Period (y) 347.5961 +/- 0.07 # Ecliptic coordinates at JD0 (AU and AU/d) Ecliptic X 32.28149268 +/- 0.0006 Ecliptic Y -18.31440561 +/- 0.0004 Ecliptic Z 7.46806531 +/- 0.0001 Ecliptic XDOT 0.00135130 +/- 0.0000 Ecliptic YDOT 0.00228241 +/- 0.0000 Ecliptic ZDOT 0.00161595 +/- 0.0000 # Distances at JD0 (AU) Heliocenter to KBO 37.85866185 +/- 0.0006 Geocenter to KBO 37.18972103 +/- 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 2025 07 29.34371 22 46 36.297 +14 53 34.82 23.9G 17QU218 G37 2025 07 29.38825 22 46 36.113 +14 53 35.09 17QU218 G37 2025 07 29.43288 22 46 35.929 +14 53 35.19 17QU218 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 0.05 0.00 -0.02
2 1.8300 0.00 -0.09 0.00 -0.11
3 1.8300 0.00 -0.06 0.00 -0.01
4 1.8301 0.00 -0.03 0.00 0.10
5 1.8354 0.00 0.06 0.00 -0.10
6 1.8354 0.00 0.09 0.00 0.01
7 1.8355 0.00 -0.03 0.00 0.13
8 1.8355 0.00 -0.00 0.00 -0.06
9 1.8597 0.00 0.14 0.00 0.03
10 1.8598 0.00 -0.11 0.00 -0.06
11 1.8599 0.00 -0.06 0.00 0.08
12 2.6515 0.00 0.08 0.00 0.11
13 2.6516 0.00 -0.17 0.00 0.02
14 2.7360 0.00 0.04 0.00 -0.02
15 2.7361 0.00 0.16 0.00 0.02
16 2.7362 0.00 0.09 0.00 -0.09
17 2.7415 0.00 0.04 0.00 0.09
18 2.7416 0.00 -0.01 0.00 -0.19
19 2.7416 0.00 -0.05 0.00 -0.00
20 2.7416 0.00 -0.09 0.00 -0.08
21 2.7470 0.00 -0.06 0.00 0.12
22 2.7470 0.00 0.08 0.00 0.07
23 2.7471 0.00 0.07 0.00 0.04
24 2.8236 0.00 0.05 0.00 0.12
25 2.8236 0.00 -0.01 0.00 0.10
26 2.8236 0.00 -0.00 0.00 -0.08
27 2.8836 0.00 -0.04 0.00 0.09
28 2.8836 0.00 0.09 0.00 -0.10
29 3.6945 0.00 -0.15 0.00 -0.13
30 3.6945 0.00 0.10 0.00 -0.01
31 3.6946 0.00 0.12 0.00 0.07
32 3.7054 0.00 -0.05 0.00 -0.11
33 3.7054 0.00 0.01 0.00 -0.04
34 3.7054 0.00 0.05 0.00 -0.04
35 3.7737 0.00 0.12 0.00 -0.25
36 3.7738 0.00 -0.03 0.00 -0.08
37 3.8556 0.00 -0.04 0.00 0.01
38 3.8556 0.00 -0.04 0.00 0.09
39 3.8584 0.00 0.04 0.00 0.21
40 3.8584 0.00 -0.09 0.00 0.11
41 3.8584 0.00 -0.02 0.00 0.09
42 11.8009 0.00 -0.61 0.00 -0.39
43 11.8010 0.00 -0.61 0.00 -0.34
44 11.8011 0.00 -0.60 0.00 -0.45
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 49.668 49.668 49.668 ecceobj 0.264 0.264 0.264 incobj 32.488 32.488 32.488 qmin 34.928 35.025 34.973 qmax 64.736 64.817 64.768 amean 49.568 49.607 49.614 amin 49.074 49.153 49.134 amax 50.141 50.179 50.174 emean 0.274 0.274 0.274 emin 0.255 0.255 0.255 emax 0.293 0.292 0.292 imean 33.625 33.632 33.625 imin 33.196 33.201 33.202 imax 34.157 34.157 34.157 excite_mean 0.618 0.618 0.618 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 155.5 154.6 154.5 kozaiamp 180.0 180.0 180.0