Orbit Fit and Astrometric record for 17DS164

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: 17DS164   
# Created Thu Oct 31 01:10:33 2024
# Orbit generated from Bernstein formalism
# Fitting     20 observations of     20
# Arc:   3.00y
# First observation: 2016/04/04
#  Last observation: 2019/04/06
Preliminary a, adot, b, bdot, g, gdot:
  -0.000120   0.022429  -0.000081   0.007359   0.023556   0.000000
# Chi-squared of fit:     6.27 DOF:     34 RMS:  0.10
# Min/Max residuals:    -0.20    0.28
# Exact a, adot, b, bdot, g, gdot:
  1.451166E-05  2.215774E-02  4.574261E-06  7.260224E-03  2.377505E-02 -3.184145E-03
# Covariance matrix:
  6.9705E-13 -8.4691E-13  1.2320E-13 -2.2266E-13 -3.4578E-13 -9.0389E-12
 -8.4691E-13  2.1500E-12 -3.9647E-13  6.9161E-13 -2.2745E-13  2.7944E-11
  1.2320E-13 -3.9647E-13  3.0223E-13 -2.8350E-13  7.3189E-14 -5.5651E-12
 -2.2266E-13  6.9161E-13 -2.8350E-13  3.8165E-13 -1.1329E-13  9.6834E-12
 -3.4578E-13 -2.2745E-13  7.3189E-14 -1.1329E-13  8.1444E-13 -4.4990E-12
 -9.0389E-12  2.7944E-11 -5.5651E-12  9.6834E-12 -4.4990E-12  3.9112E-10
#      lat0       lon0       xBary       yBary       zBary        JD0
    4.040987 -171.967707   -0.117551    0.069841   -0.986747  2457482.943323
# Heliocentric elements and errors
Epoch:              2457480.5000  =  2016/04/02
Mean Anomaly:          306.65414 +/-     0.090
Argument of Peri:       81.35783 +/-     0.181
Long of Asc Node:      176.27236 +/-     0.001
Inclination:            18.47757 +/-     0.001
Eccentricity:         0.15127241 +/-    0.0008
Semi-Major Axis:     46.46926999 +/-    0.0081
Time of Perihelion: 2474625.8137 +/-      28.6
Perihelion:          39.43975169 +/-    0.0361
Aphelion:            53.49878829 +/-    0.0367
Period (y)              316.7794 +/-      0.08
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -42.51147770 +/-    0.0016
Ecliptic Y           -6.11989362 +/-    0.0002
Ecliptic Z            2.96425802 +/-    0.0001
Ecliptic XDOT         0.00077718 +/-    0.0000
Ecliptic YDOT        -0.00247422 +/-    0.0000
Ecliptic ZDOT         0.00080815 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   43.05189496 +/-    0.0016
Geocenter to KBO     42.06090311 +/-    0.0016
# Hcoef:  7.74

The following table shows the complete astrometric record for 17DS164. 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 (17DS164) followed by the observatory code and reference code for the source of the astrometry.

2016 04  04.442534 12 35 52.84   +00 31 40.0         17DS164   T09  C~83F2      
2016 04  04.555772 12 35 52.34   +00 31 43.6         17DS164   T09  C~83F2      
2017 02  21.49546  12 44 00.62   +00 02 12.7   23.6z 17DS164   T09  C~81Bw      
2017 02  21.49884  12 44 00.62   +00 02 12.7   23.7z 17DS164   T09  C~81Bw      
2017 02  21.54460  12 44 00.49   +00 02 14.1   23.6z 17DS164   T09  C~81Bw      
2017 02  21.56614  12 44 00.40   +00 02 14.8   23.6z 17DS164   T09  C~81Bw      
2017 02  21.59574  12 44 00.31   +00 02 15.4   23.8z 17DS164   T09  C~81Bw      
2017 02  21.60643  12 44 00.27   +00 02 15.8   23.7z 17DS164   T09  C~81Bw      
2017 02  21.61716  12 44 00.24   +00 02 16.1   23.8z 17DS164   T09  C~81Bw      
2017 02  23.54142  12 43 54.10   +00 03 12.2   24.6r 17DS164   T09  C~81Bw      
2017 02  23.54421  12 43 54.08   +00 03 12.2   24.7r 17DS164   T09  C~81Bw      
2017 02  23.57824  12 43 53.97   +00 03 13.0   24.5r 17DS164   T09  C~81Bw      
2017 02  23.61219  12 43 53.86   +00 03 14.2   24.4r 17DS164   T09  C~81Bw      
2017 02  23.65456  12 43 53.72   +00 03 15.2   24.1r 17DS164   T09  C~81Bw      
2017 03  04.55244  12 43 22.68   +00 07 45.8   23.4y 17DS164   T09  C~81Bw      
2017 03  04.55518  12 43 22.67   +00 07 46.0   23.7y 17DS164   T09  C~81Bw      
2017 03  04.59585  12 43 22.51   +00 07 47.2   23.6y 17DS164   T09  C~81Bw      
2017 04  27.392208 12 39 40.97   +00 35 22.8         17DS164   T09  C~83F2      
2019 04  03.429182 12 52 09.80   +00 09 06.2         17DS164   T09  C~83F2      
2019 04  06.473958 12 51 56.58   +00 10 42.8         17DS164   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     0.05       0.00     0.05
     2   0.0003     -8.31    -0.07       0.35     0.06
     3   0.8845   7424.37    -0.11    1258.91     0.00
     4   0.8845   7424.37     0.08    1258.91    -0.02
     5   0.8846   7422.03     0.28    1259.43     0.15
     6   0.8847   7420.51    -0.04    1259.54     0.10
     7   0.8847   7419.03     0.13    1259.56    -0.10
     8   0.8848   7418.32     0.02    1259.69    -0.05
     9   0.8848   7417.78     0.09    1259.79    -0.03
    10   0.8901   7310.89    -0.00    1275.06     0.13
    11   0.8901   7310.62    -0.12    1274.94    -0.01
    12   0.8902   7308.78     0.01    1275.02    -0.17
    13   0.8903   7306.79    -0.03    1275.48     0.03
    14   0.8904   7304.46     0.07    1275.57    -0.19
    15   0.9147   6769.28    -0.10    1340.78    -0.07
    16   0.9148   6769.06    -0.14    1340.91     0.03
    17   0.9149   6766.38    -0.20    1341.06    -0.07
    18   1.0621   3057.56     0.09    1552.99     0.09
    19   2.9952  14025.36    -0.04    4538.98    -0.00
    20   3.0035  13803.99     0.03    4549.43     0.05

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.

17DS164    quality flag:3

Type:       SCATEXTD  SCATEXTD  SCATEXTD

axisobj        45.939    45.960    45.919
ecceobj         0.146     0.147     0.146
incobj         18.575    18.576    18.575
qmin           38.815    38.815    38.820
qmax           53.911    53.984    53.881
amean          46.204    46.224    46.189
amin           45.827    45.832    45.805
amax           46.632    46.675    46.619
emean           0.143     0.143     0.143
emin            0.131     0.131     0.131
emax            0.157     0.158     0.157
imean          18.306    18.304    18.297
imin           17.917    17.920    17.920
imax           18.600    18.595    18.562
excite_mean     0.345     0.345     0.345
fracstop        1.000     1.000     1.000
cjmean          2.980     2.980     2.980

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       177.5     177.3     177.1
kozaiamp        180.0     180.0     180.0