Orbit Fit and Astrometric record for 12GX17

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: 12GX17    
# Created Sun Oct 22 01:38:10 2017
# Orbit generated from Bernstein formalism
# Fitting   20 observations of   20
# Arc:   2.92y
# First observation: 2012/04/14
#  Last observation: 2015/03/16
Preliminary a, adot, b, bdot, g, gdot:
   0.000439   0.032453   0.000241   0.019956   0.035982   0.000000
# Chi-squared of fit:    26.08 DOF:   34 RMS:  0.20
# Min/Max residuals:    -0.41    0.34
# Exact a, adot, b, bdot, g, gdot:
  1.594614E-05  3.476517E-02  1.016436E-05  2.118370E-02  3.610959E-02  2.370480E-02
# Covariance matrix:
  1.4091E-13 -1.7589E-13  1.1570E-14 -5.6819E-14 -7.3177E-15 -1.0878E-12
 -1.7589E-13  7.0217E-13 -5.8230E-14  2.9072E-13 -1.9568E-13  5.5525E-12
  1.1570E-14 -5.8230E-14  1.2598E-13 -9.8865E-14 -6.8246E-15 -5.9238E-13
 -5.6819E-14  2.9072E-13 -9.8865E-14  2.5729E-13  1.0540E-14  2.9114E-12
 -7.3177E-15 -1.9568E-13 -6.8246E-15  1.0540E-14  1.1289E-12  2.6648E-13
 -1.0878E-12  5.5525E-12 -5.9238E-13  2.9114E-12  2.6648E-13  5.5734E-11
#      lat0       lon0       xBary       yBary       zBary        JD0
   -9.513359 -165.822821   -0.182660   -0.163579   -0.976042  2456031.839716
# Heliocentric elements and errors
Epoch:              2456030.5000  =  2012/04/13
Mean Anomaly:           36.19827 +/-     0.020
Argument of Peri:      243.53326 +/-     0.012
Long of Asc Node:      209.19167 +/-     0.000
Inclination:            32.60407 +/-     0.000
Eccentricity:         0.55009207 +/-    0.0002
Semi-Major Axis:     37.47870498 +/-    0.0132
Time of Perihelion: 2447603.7404 +/-       1.5
Perihelion:          16.86196666 +/-    0.0088
Aphelion:            58.09544329 +/-    0.0215
Period (y)              229.4484 +/-      0.12
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -27.39270180 +/-    0.0008
Ecliptic Y           -7.10759407 +/-    0.0002
Ecliptic Z           -4.57680968 +/-    0.0001
Ecliptic XDOT        -0.00133534 +/-    0.0000
Ecliptic YDOT        -0.00305109 +/-    0.0000
Ecliptic ZDOT         0.00128712 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   28.66749365 +/-    0.0007
Geocenter to KBO     27.69347199 +/-    0.0008
# Hcoef:  7.97

The following table shows the complete astrometric record for 12GX17. 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 (12GX17) followed by the observatory code and reference code for the source of the astrometry.

2012 04  14.33895  12 37 02.077  -14 20 34.21  22.3w 12GX17    F51  C~0frl      
2012 04  14.36865  12 37 01.879  -14 20 32.60  22.3w 12GX17    F51  C~0frl      
2012 04  14.38348  12 37 01.780  -14 20 31.87  22.2w 12GX17    F51  C~0frl      
2012 04  18.17323  12 36 38.25   -14 16 56.4   22.5R 12GX17    H01  C~0frl      
2012 04  18.19007  12 36 38.16   -14 16 55.5   22.6R 12GX17    H01  C~0frl      
2012 04  18.20451  12 36 38.08   -14 16 54.5   22.3R 12GX17    H01  C~0frl      
2012 04  18.22192  12 36 37.97   -14 16 53.5   21.8R 12GX17    H01  C~0frl      
2012 04  18.26365  12 36 37.71   -14 16 51.1   22.7R 12GX17    H01  C~0frl      
2012 04  18.27894  12 36 37.60   -14 16 50.5   21.9R 12GX17    H01  C~0frl      
2012 04  18.30916  12 36 37.42   -14 16 48.6   21.7R 12GX17    H01  C~0frl      
2013 03  16.26319  12 49 26.033  -14 25 13.53  22.7r 12GX17    807  C~12zi      
2013 03  16.26319  12 49 26.00   -14 25 14.0   22.4r 12GX17    W84  C~2J9V      
2013 03  16.31084  12 49 25.756  -14 25 11.68  22.7r 12GX17    807  C~12zi      
2013 03  16.31085  12 49 25.72   -14 25 11.9         12GX17    W84  C~2J9V      
2013 03  16.37053  12 49 25.370  -14 25 09.00  22.7r 12GX17    807  C~12zi      
2013 03  16.37053  12 49 25.34   -14 25 09.4         12GX17    W84  C~2J9V      
2013 05  09.08731  12 44 01.334  -13 38 50.50  22.7r 12GX17    807  C~12zi      
2013 05  10.13299  12 43 56.334  -13 37 55.55  22.7r 12GX17    807  C~12zi      
2015 03  16.30954  13 06 38.93   -13 43 52.1   22.1R 12GX17    G37  C~1N7Y      
2015 03  16.38737  13 06 38.49   -13 43 48.9         12GX17    G37  C~1N7Y      

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    -0.15       0.00    -0.18
  2   0.0001     -3.28    -0.22       0.33    -0.29
  3   0.0001     -4.89    -0.23       0.43    -0.41
  4   0.0105   -404.41    -0.10      61.87    -0.04
  5   0.0105   -405.97     0.12      62.17    -0.01
  6   0.0106   -407.43     0.19      62.62     0.21
  7   0.0106   -409.30     0.17      62.90     0.21
  8   0.0107   -413.72     0.17      63.60     0.24
  9   0.0108   -415.43     0.08      63.51    -0.10
 10   0.0109   -418.58     0.12      64.21     0.11
 11   0.9197  10063.29    -0.25    3982.34    -0.34
 12   0.9197  10063.56     0.01    3982.95     0.28
 13   0.9198  10059.12     0.33    3983.11     0.20
 14   0.9198  10058.72    -0.07    3982.70    -0.20
 15   0.9200  10052.89     0.06    3983.41     0.21
 16   0.9200  10052.65    -0.19    3982.88    -0.33
 17   1.0671   4620.28    -0.20    4710.32     0.34
 18   1.0699   4531.65     0.07    4732.36     0.29
 19   2.9185  23156.42     0.02   12013.20    -0.17
 20   2.9187  23149.18     0.06   12013.79    -0.01

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.

12GX17    quality flag:3

Type:       CENTAURR  CENTAURR  CENTAURR

axisobj        37.526    37.567    37.485
ecceobj         0.550     0.551     0.550
incobj         32.585    32.585    32.586
qmin           16.746    16.738    16.770
qmax           58.482    59.392    58.442
amean          37.037    37.659    37.091
amin           36.553    36.854    36.514
amax           37.707    38.300    37.794
emean           0.524     0.534     0.529
emin            0.493     0.523     0.511
emax            0.551     0.551     0.550
imean          34.244    33.853    33.889
imin           32.904    32.872    32.901
imax           35.866    34.433    34.823
excite_mean     0.769     0.772     0.769
fracstop        0.018     0.041     0.018
cjmean          2.384     2.381     2.385

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       252.8     265.1     252.8
kozaiamp          9.2      21.5       9.3