Orbit Fit and Astrometric record for 17DU164

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: 17DU164   
# Created Tue Apr  1 01:11:04 2025
# Orbit generated from Bernstein formalism
# Fitting     19 observations of     19
# Arc:   3.00y
# First observation: 2016/04/04
#  Last observation: 2019/04/06
Preliminary a, adot, b, bdot, g, gdot:
  -0.000040   0.023923  -0.000002   0.000152   0.024195   0.000000
# Chi-squared of fit:    11.31 DOF:     32 RMS:  0.14
# Min/Max residuals:    -0.50    0.25
# Exact a, adot, b, bdot, g, gdot:
  1.576550E-05  2.389402E-02 -8.013790E-08  1.503333E-04  2.438251E-02  2.149955E-04
# Covariance matrix:
  7.3290E-13 -9.6767E-13  2.0156E-15 -4.9662E-15 -3.1650E-13 -1.0103E-11
 -9.6767E-13  2.5239E-12 -1.7815E-14  1.7691E-14 -3.3090E-13  3.1381E-11
  2.0156E-15 -1.7815E-14  2.3203E-13 -1.4922E-13  1.0541E-14 -2.4789E-13
 -4.9662E-15  1.7691E-14 -1.4922E-13  1.4432E-13 -4.6545E-15  2.3681E-13
 -3.1650E-13 -3.3090E-13  1.0541E-14 -4.6545E-15  8.8973E-13 -5.7202E-12
 -1.0103E-11  3.1381E-11 -2.4789E-13  2.3681E-13 -5.7202E-12  4.1600E-10
#      lat0       lon0       xBary       yBary       zBary        JD0
    3.569629 -171.827643   -0.115132    0.061739   -0.987572  2457482.943323
# Heliocentric elements and errors
Epoch:              2457480.5000  =  2016/04/02
Mean Anomaly:           23.20562 +/-     1.312
Argument of Peri:       59.67153 +/-     1.404
Long of Asc Node:      104.06429 +/-     0.015
Inclination:             3.50274 +/-     0.000
Eccentricity:         0.02979638 +/-    0.0005
Semi-Major Axis:     43.18107640 +/-    0.0107
Time of Perihelion: 2450799.6879 +/-     377.6
Perihelion:          41.89443665 +/-    0.0248
Aphelion:            44.46771614 +/-    0.0251
Period (y)              283.7582 +/-      0.11
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -41.48451796 +/-    0.0016
Ecliptic Y           -6.07606621 +/-    0.0002
Ecliptic Z            2.55355819 +/-    0.0001
Ecliptic XDOT         0.00035871 +/-    0.0000
Ecliptic YDOT        -0.00266601 +/-    0.0000
Ecliptic ZDOT         0.00001836 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   42.00481485 +/-    0.0015
Geocenter to KBO     41.01300707 +/-    0.0016
# Hcoef:  7.24

The following table shows the complete astrometric record for 17DU164. 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 (17DU164) followed by the observatory code and reference code for the source of the astrometry.

2016 04  04.442534 12 35 39.12   +00 02 22.1         17DU164   T09  C~83F2      
2016 04  04.555772 12 35 38.61   +00 02 25.1         17DU164   T09  C~83F2      
2017 02  21.48870  12 43 36.19   -00 49 15.7   22.9z 17DU164   T09  C~81Bw      
2017 02  21.51504  12 43 36.10   -00 49 15.2   22.9z 17DU164   T09  C~81Bw      
2017 02  21.53656  12 43 36.02   -00 49 14.7   22.9z 17DU164   T09  C~81Bw      
2017 02  21.55809  12 43 35.94   -00 49 14.1   22.9z 17DU164   T09  C~81Bw      
2017 02  21.60643  12 43 35.78   -00 49 12.8   23.1z 17DU164   T09  C~81Bw      
2017 02  23.53005  12 43 29.36   -00 48 24.9   23.9r 17DU164   T09  C~81Bw      
2017 02  23.56973  12 43 29.22   -00 48 23.7   24.2r 17DU164   T09  C~81Bw      
2017 02  23.61219  12 43 29.07   -00 48 22.7   23.9r 17DU164   T09  C~81Bw      
2017 02  23.64192  12 43 28.97   -00 48 22.2   23.8r 17DU164   T09  C~81Bw      
2017 03  04.54160  12 42 56.54   -00 44 27.5   22.9y 17DU164   T09  C~81Bw      
2017 03  04.58243  12 42 56.38   -00 44 26.2   23.1y 17DU164   T09  C~81Bw      
2017 03  04.59585  12 42 56.34   -00 44 25.7   23.1y 17DU164   T09  C~81Bw      
2017 03  04.63107  12 42 56.17   -00 44 24.6   23.6y 17DU164   T09  C~81Bw      
2017 03  04.63382  12 42 56.18   -00 44 24.6   23.2y 17DU164   T09  C~81Bw      
2017 04  27.380876 12 39 06.14   -00 19 50.4         17DU164   T09  C~83F2      
2019 04  06.460461 12 50 43.57   -01 32 41.9         17DU164   T09  C~83F2      
2019 04  06.501697 12 50 43.38   -01 32 40.7         17DU164   T09  C~83F2      

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    -0.06       0.00     0.04
     2   0.0003     -8.21     0.06      -0.25    -0.12
     3   0.8845   7801.22     0.21     -30.65     0.10
     4   0.8845   7799.78     0.25     -30.72    -0.04
     5   0.8846   7798.48     0.16     -30.74    -0.11
     6   0.8846   7797.14     0.03     -30.66    -0.09
     7   0.8848   7794.42     0.02     -30.41     0.02
     8   0.8900   7686.90     0.07     -24.26     0.01
     9   0.8901   7684.49    -0.03     -23.98     0.18
    10   0.8903   7682.03    -0.03     -23.95     0.10
    11   0.8903   7680.45     0.11     -24.08    -0.11
    12   0.9147   7140.23    -0.08       0.28    -0.22
    13   0.9148   7137.51    -0.14       0.53    -0.05
    14   0.9149   7136.76    -0.02       0.75     0.15
    15   0.9150   7133.98    -0.50       0.76     0.09
    16   0.9150   7134.12    -0.19       0.82     0.14
    17   1.0621   3379.41     0.13      -2.23    -0.06
    18   3.0035  14740.32     0.02      93.89    -0.03
    19   3.0036  14737.21    -0.02      93.88    -0.00

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.

17DU164    quality flag:3

Type:      CLASSICAL CLASSICAL CLASSICAL

axisobj        42.729    42.765    42.694
ecceobj         0.021     0.023     0.019
incobj          3.502     3.502     3.502
qmin           40.796    40.689    40.797
qmax           45.272    45.430    45.142
amean          42.941    42.977    42.906
amin           42.614    42.650    42.579
amax           43.283    43.327    43.239
emean           0.028     0.029     0.026
emin            0.008     0.010     0.006
emax            0.047     0.049     0.044
imean           2.002     2.006     1.999
imin            1.019     1.029     1.009
imax            2.904     2.893     2.918
excite_mean     0.045     0.046     0.043
fracstop        1.000     1.000     1.000
cjmean          3.087     3.087     3.086

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       188.1     187.3     189.0
kozaiamp        180.0     180.0     180.0