Orbit Fit and Astrometric record for 17GY8

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: 17GY8     
# Created Mon Oct 23 01:38:42 2017
# Orbit generated from Bernstein formalism
# Fitting   30 observations of   30
# Arc:  47.05d
# First observation: 2017/03/05
#  Last observation: 2017/04/21
Preliminary a, adot, b, bdot, g, gdot:
  -0.000154   0.334719   0.000030  -0.061657   0.127579   0.000000
# Chi-squared of fit:    24.94 DOF:   54 RMS:  0.16
# Min/Max residuals:    -0.39    0.45
# Exact a, adot, b, bdot, g, gdot:
  4.303249E-05  3.557654E-01 -6.928399E-06 -6.184873E-02  1.309772E-01  5.392167E-02
# Covariance matrix:
  3.4275E-13  3.3315E-13  6.7525E-15 -7.5549E-13  1.3815E-12  9.7817E-11
  3.3315E-13  3.7601E-08 -6.4442E-11 -4.1629E-10  6.2382E-09  1.3414E-08
  6.7525E-15 -6.4442E-11  3.3487E-13 -1.5106E-12 -1.0609E-11 -1.4046E-11
 -7.5549E-13 -4.1629E-10 -1.5106E-12  3.5658E-11 -7.5022E-11 -7.4026E-10
  1.3815E-12  6.2382E-09 -1.0609E-11 -7.5022E-11  1.0435E-09  3.0139E-09
  9.7817E-11  1.3414E-08 -1.4046E-11 -7.4026E-10  3.0139E-09  8.3573E-08
#      lat0       lon0       xBary       yBary       zBary        JD0
   11.362780 -168.413098    0.449336    0.173945   -0.864875  2457818.017121
# Heliocentric elements and errors
Epoch:              2457810.5000  =  2017/02/26
Mean Anomaly:            1.89814 +/-     0.015
Argument of Peri:      117.21775 +/-     0.108
Long of Asc Node:       56.41761 +/-     0.016
Inclination:            13.59945 +/-     0.004
Eccentricity:         0.68332294 +/-    0.0007
Semi-Major Axis:     26.56675182 +/-    0.0524
Time of Perihelion: 2457546.7863 +/-       1.9
Perihelion:           8.41308080 +/-    0.0253
Aphelion:            44.72042283 +/-    0.0903
Period (y)              136.9354 +/-      0.41
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X           -8.29033834 +/-    0.0018
Ecliptic Y           -1.24514490 +/-    0.0004
Ecliptic Z            1.50419850 +/-    0.0004
Ecliptic XDOT         0.00016490 +/-    0.0000
Ecliptic YDOT        -0.00756486 +/-    0.0000
Ecliptic ZDOT        -0.00104550 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO    8.51720076 +/-    0.0018
Geocenter to KBO      7.63491784 +/-    0.0019
# Hcoef: 13.12

The following table shows the complete astrometric record for 17GY8. 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 (17GY8) followed by the observatory code and reference code for the source of the astrometry.

2017 03  05.51632  13 00 22.625  +05 52 45.58  23.2w 17GY8     F51  C~2F9C      
2017 03  05.52904  13 00 22.455  +05 52 46.58  23.3w 17GY8     F51  C~2F9C      
2017 03  05.54177  13 00 22.292  +05 52 48.04  22.8w 17GY8     F51  C~2F9C      
2017 03  05.55452  13 00 22.119  +05 52 49.22  22.7w 17GY8     F51  C~2F9C      
2017 03  20.34600  12 56 43.110  +06 15 04.99  22.5w 17GY8     F51  C~2F9C      
2017 03  20.35785  12 56 42.913  +06 15 05.76  22.1w 17GY8     F51  C~2F9C      
2017 03  20.38156  12 56 42.514  +06 15 07.42  22.3w 17GY8     F51  C~2F9C      
2017 03  29.39959  12 54 10.862  +06 27 30.16  22.5w 17GY8     F51  C~2F9C      
2017 03  29.41185  12 54 10.648  +06 27 31.35  22.5w 17GY8     F51  C~2F9C      
2017 03  29.42541  12 54 10.415  +06 27 32.02  22.8w 17GY8     F51  C~2F9C      
2017 03  29.43773  12 54 10.186  +06 27 33.18  23.2w 17GY8     F51  C~2F9C      
2017 04  03.46951  12 52 43.193  +06 33 40.06  21.9w 17GY8     F51  C~2F9C      
2017 04  03.48341  12 52 42.942  +06 33 40.99  22.2w 17GY8     F51  C~2F9C      
2017 04  03.49732  12 52 42.691  +06 33 41.90  22.0w 17GY8     F51  C~2F9C      
2017 04  03.51127  12 52 42.451  +06 33 42.97  22.0w 17GY8     F51  C~2F9C      
2017 04  04.297409 12 52 28.908  +06 34 36.17  22.0G 17GY8     568  C~2F9C      
2017 04  04.298420 12 52 28.890  +06 34 36.30  21.8G 17GY8     568  C~2F9C      
2017 04  04.299402 12 52 28.880  +06 34 36.31  21.9G 17GY8     568  C~2F9C      
2017 04  16.30952  12 49 04.615  +06 45 39.45  22.1w 17GY8     F51  C~2F9C      
2017 04  16.33362  12 49 04.224  +06 45 40.48  22.2w 17GY8     F51  C~2F9C      
2017 04  16.34570  12 49 04.018  +06 45 41.04  21.9w 17GY8     F51  C~2F9C      
2017 04  20.37350  12 47 58.923  +06 48 10.37  22.7w 17GY8     F51  C~2F9C      
2017 04  20.39487  12 47 58.572  +06 48 11.11  22.6w 17GY8     F51  C~2F9C      
2017 04  20.40559  12 47 58.384  +06 48 11.42  22.6w 17GY8     F51  C~2F9C      
2017 04  21.424071 12 47 42.353  +06 48 42.48  22.2G 17GY8     568  C~2F9C      
2017 04  21.425286 12 47 42.334  +06 48 42.53  22.1G 17GY8     568  C~2F9C      
2017 04  21.426497 12 47 42.313  +06 48 42.50  22.2G 17GY8     568  C~2F9C      
2017 04  21.55476  12 47 40.28   +06 48 47.6         17GY8     Q62  C~2F9C      
2017 04  21.56082  12 47 40.20   +06 48 47.9         17GY8     Q62  C~2F9C      
2017 04  21.56689  12 47 40.10   +06 48 48.0   22.1w 17GY8     Q62  C~2F9C      

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    -0.02       0.00    -0.11
  2   0.0000     -2.73     0.06      -0.07    -0.25
  3   0.0001     -5.54     0.06       0.32     0.08
  4   0.0001     -8.37     0.04       0.39     0.09
  5   0.0406  -3537.68    -0.21     -47.33     0.45
  6   0.0406  -3540.69    -0.11     -47.77     0.20
  7   0.0407  -3546.81    -0.02     -48.56    -0.21
  8   0.0654  -5919.62    -0.12    -245.44    -0.21
  9   0.0654  -5923.02    -0.18    -245.58     0.03
 10   0.0655  -5926.49     0.05    -246.32    -0.28
 11   0.0655  -5930.08    -0.19    -246.58    -0.15
 12   0.0793  -7268.60     0.18    -412.64     0.17
 13   0.0793  -7272.41     0.13    -413.24     0.13
 14   0.0793  -7276.21     0.09    -413.86     0.06
 15   0.0794  -7279.93     0.15    -414.26     0.22
 16   0.0815  -7486.83     0.08    -443.63    -0.04
 17   0.0815  -7487.13     0.05    -443.62     0.01
 18   0.0815  -7487.27     0.17    -443.67     0.00
 19   0.1144 -10555.68    -0.21   -1012.44    -0.17
 20   0.1145 -10561.46    -0.01   -1013.74    -0.07
 21   0.1145 -10564.52    -0.06   -1014.41    -0.04
 22   0.1256 -11519.26     0.10   -1251.90     0.04
 23   0.1256 -11524.39     0.04   -1253.24     0.08
 24   0.1256 -11527.10    -0.13   -1254.04    -0.03
 25   0.1284 -11760.10     0.27   -1317.73    -0.10
 26   0.1284 -11760.38     0.27   -1317.80    -0.08
 27   0.1284 -11760.66     0.28   -1317.95    -0.15
 28   0.1288 -11790.66    -0.39   -1324.95    -0.01
 29   0.1288 -11791.88    -0.20   -1325.13     0.20
 30   0.1288 -11793.29    -0.21   -1325.62     0.12

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.

17GY8    quality flag:3

Type:       CENTAURR  CENTAURR  CENTAURR

axisobj        26.303    26.843    25.784
ecceobj         0.677     0.681     0.674
incobj         13.557    13.566    13.548
qmin            8.408     8.345     8.415
qmax           44.994    45.133    48.186
amean          26.502    24.733    27.229
amin           26.303    23.771    25.784
amax           26.701    26.843    28.311
emean           0.681     0.660     0.690
emin            0.677     0.649     0.674
emax            0.685     0.681     0.702
imean          12.616    13.269    12.524
imin           12.609    12.631    12.455
imax           12.623    13.680    12.615
excite_mean     0.715     0.698     0.723
fracstop        0.000     0.000     0.000
cjmean          2.472     2.542     2.448

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       117.5     118.6     121.6
kozaiamp          1.3       3.7       3.9