Orbit Fit and Astrometric record for 15GR50

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: 15GR50    
# Created Tue Dec 12 02:38:13 2017
# Orbit generated from Bernstein formalism
# Fitting   12 observations of   13
# Arc:   1.06y
# First observation: 2015/04/13
#  Last observation: 2016/05/03
Preliminary a, adot, b, bdot, g, gdot:
  -0.000002   0.009563  -0.000002  -0.000753   0.014833   0.000000
# Chi-squared of fit:    15.25 DOF:   18 RMS:  0.20
# Min/Max residuals:    -0.34    0.41
# Exact a, adot, b, bdot, g, gdot:
  1.181573E-05  9.591564E-03 -2.771964E-06 -7.555194E-04  1.489338E-02  1.299256E-03
# Covariance matrix:
  2.7551E-13  3.7574E-13  1.0883E-15 -5.4351E-14  8.4318E-13  7.1022E-11
  3.7574E-13  5.7365E-12  9.3549E-15 -4.6442E-13  5.8418E-12  6.0738E-10
  1.0883E-15  9.3549E-15  1.9095E-13 -2.0170E-13  1.0999E-14  1.1103E-12
 -5.4351E-14 -4.6442E-13 -2.0170E-13  6.3358E-13 -5.4909E-13 -5.5166E-11
  8.4318E-13  5.8418E-12  1.0999E-14 -5.4909E-13  8.4141E-12  7.1755E-10
  7.1022E-11  6.0738E-10  1.1103E-12 -5.5166E-11  7.1755E-10  7.2139E-08
#      lat0       lon0       xBary       yBary       zBary        JD0
   -0.113657 -156.254569    0.017380   -0.001828   -0.999570  2457125.623078
# Heliocentric elements and errors
Epoch:              2457120.5000  =  2015/04/08
Mean Anomaly:          145.86879 +/-     3.796
Argument of Peri:       21.24340 +/-     3.694
Long of Asc Node:       22.30242 +/-     0.002
Inclination:             4.49172 +/-     0.005
Eccentricity:         0.29354333 +/-    0.0069
Semi-Major Axis:     53.97749402 +/-    0.2259
Time of Perihelion: 2398428.7065 +/-    1482.2
Perihelion:          38.13276076 +/-    0.4032
Aphelion:            69.82222728 +/-    0.4717
Period (y)              396.5768 +/-      2.49
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -62.38449337 +/-    0.0120
Ecliptic Y          -27.42407899 +/-    0.0052
Ecliptic Z           -0.13338611 +/-    0.0000
Ecliptic XDOT         0.00048844 +/-    0.0000
Ecliptic YDOT        -0.00171595 +/-    0.0000
Ecliptic ZDOT        -0.00013928 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   68.14633455 +/-    0.0112
Geocenter to KBO     67.14393890 +/-    0.0131
# Hcoef:  6.69

The following table shows the complete astrometric record for 15GR50. 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 (15GR50) followed by the observatory code and reference code for the source of the astrometry.

2015 04  13.12230  13 27 44.935  -09 19 21.57  24.8r 15GR50    807  C~1x8u      
2015 04  13.21164  13 27 44.701  -09 19 20.69        15GR50    807  C~1x8u      
2015 04  13.30360  13 27 44.399  -09 19 19.34        15GR50    807  C~1x8u      
2015 04  18.11853  13 27 30.078  -09 17 56.90        15GR50    304  C~1x8u      
2015 04  18.28707  13 27 29.549  -09 17 54.09        15GR50    304  C~1x8u      
2015 04  19.18541  13 27 26.899  -09 17 38.79        15GR50    304  C~1x8u      
2015 04  19.28954  13 27 26.644  -09 17 36.50  24.8r 15GR50    304  C~1x8u      
2015 04  20.26896  13 27 23.684  -09 17 20.31        15GR50    304  C~1x8u      
2015 05  22.15568  13 25 57.608  -09 09 06.92        15GR50    304  C~1x8u      
2016 03  09.35707  13 31 19.373  -09 42 47.02        15GR50    304  C~1x8u      
2016 03  10.23738  13 31 17.306  -09 42 35.22        15GR50    304  C~1x8u      
2016 05  03.05166  13 28 45.232  -09 28 12.11  24.8r 15GR50    304  C~2AE2      
2016 05  03.17184  13 28 44.853  -09 28 10.05        15GR50    304  C~2AE2      

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    -0.34       0.00     0.41
  2   0.0002     -3.54     0.40      -0.46     0.01
  3   0.0005     -8.20     0.15      -0.85    -0.33
  4   0.0137   -235.64     0.06      -2.47     0.08
  5   0.0141   -243.96    -0.20      -2.75    -0.08
  6   0.0166   -286.06    -0.04      -3.01     0.01
  7   0.0169   -290.42 (   0.57)     -2.28 (   0.82)
  8   0.0196   -337.12    -0.07      -3.41     0.09
  9   0.1069  -1703.72     0.05     -16.10    -0.17
 10   0.9069   3467.17    -0.05    -140.23    -0.26
 11   0.9093   3434.40     0.05    -140.46    -0.06
 12   1.0566   1025.06     0.28    -164.23     0.18
 13   1.0569   1019.09    -0.29    -164.38     0.11

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.

15GR50    quality flag:3

Type:       SCATNEAR  SCATNEAR  SCATNEAR

axisobj        53.520    54.367    53.083
ecceobj         0.303     0.325     0.290
incobj          4.524     4.524     4.524
qmin           37.021    36.333    37.481
qmax           71.473    74.249    70.162
amean          53.840    54.731    53.424
amin           53.266    54.078    52.879
amax           54.508    55.572    54.077
emean           0.299     0.323     0.286
emin            0.288     0.310     0.274
emax            0.311     0.337     0.298
imean           4.335     4.392     4.272
imin            3.840     3.894     3.889
imax            4.745     4.897     4.669
excite_mean     0.309     0.332     0.295
fracstop        1.000     1.000     1.000
cjmean          3.104     3.094     3.109

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       175.7     179.8     172.4
kozaiamp        179.9     180.0     179.9