Orbit Fit and Astrometric record for 08LD18

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: 08LD18    
# Created Sat Oct 21 01:37:45 2017
# Orbit generated from Bernstein formalism
# Fitting   10 observations of   10
# Arc:  76.62d
# First observation: 2008/06/07
#  Last observation: 2008/08/23
Preliminary a, adot, b, bdot, g, gdot:
  -0.000002   0.061418  -0.000011  -0.010139   0.037554   0.000000
# Chi-squared of fit:     3.21 DOF:   14 RMS:  0.10
# Min/Max residuals:    -0.13    0.31
# Exact a, adot, b, bdot, g, gdot:
  1.978049E-05  4.190597E-02 -5.016017E-06 -1.069544E-02  3.437265E-02  8.156918E-03
# Covariance matrix:
  3.1926E-13  4.3102E-11 -2.1658E-14  1.2780E-12  7.2318E-12 -1.8320E-10
  4.3102E-11  1.2057E-07 -6.5929E-11  4.1971E-09  1.7848E-08 -8.0803E-07
 -2.1658E-14 -6.5929E-11  2.9971E-13 -3.7794E-12 -9.7172E-12  4.4989E-10
  1.2780E-12  4.1971E-09 -3.7794E-12  1.6665E-10  6.1698E-10 -2.8937E-08
  7.2318E-12  1.7848E-08 -9.7172E-12  6.1698E-10  2.6526E-09 -1.1777E-07
 -1.8320E-10 -8.0803E-07  4.4989E-10 -2.8937E-08 -1.1777E-07  5.7556E-06
#      lat0       lon0       xBary       yBary       zBary        JD0
    3.352761  -85.488294    0.307108    0.056304   -0.960978  2454624.935154
# Heliocentric elements and errors
Epoch:              2454620.5000  =  2008/06/03
Mean Anomaly:           24.16275 +/-     4.510
Argument of Peri:      121.66499 +/-    10.288
Long of Asc Node:      106.52319 +/-     0.102
Inclination:            14.57173 +/-     0.112
Eccentricity:         0.30454946 +/-    0.0392
Semi-Major Axis:     40.22711932 +/-    0.7385
Time of Perihelion: 2448365.5967 +/-    1154.7
Perihelion:          27.97597166 +/-    1.6594
Aphelion:            52.47826698 +/-    1.8487
Period (y)              255.1447 +/-      7.03
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X            2.05561468 +/-    0.0034
Ecliptic Y          -29.94179834 +/-    0.0434
Ecliptic Z            1.70135067 +/-    0.0026
Ecliptic XDOT         0.00338884 +/-    0.0000
Ecliptic YDOT        -0.00043273 +/-    0.0002
Ecliptic ZDOT        -0.00081257 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   30.06046297 +/-    0.0432
Geocenter to KBO     29.09289820 +/-    0.0436
# Hcoef:  8.41

The following table shows the complete astrometric record for 08LD18. 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 (08LD18) followed by the observatory code and reference code for the source of the astrometry.

2008 06  07.43440  18 19 10.567  -20 00 41.33  23. r 08LD18    568  C~0gaI      
2008 06  07.47281  18 19 10.322  -20 00 41.62        08LD18    568  C~0gaI      
2008 06  07.51113  18 19 10.063  -20 00 41.84        08LD18    568  C~0gaI      
2008 06  08.34093  18 19 04.721  -20 00 47.44        08LD18    304  C~0gaI      
2008 06  08.36290  18 19 04.602  -20 00 47.53        08LD18    304  C~0gaI      
2008 07  09.13333  18 15 37.945  -20 05 14.36        08LD18    807  C~0gaI      
2008 07  09.19028  18 15 37.564  -20 05 15.17        08LD18    807  C~0gaI      
2008 08  21.98611  18 11 56.171  -20 13 37.51        08LD18    304  C~0gaI      
2008 08  22.07292  18 11 55.921  -20 13 38.57        08LD18    304  C~0gaI      
2008 08  23.05555  18 11 53.121  -20 13 50.82        08LD18    304  C~0gaI      

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    -0.10       0.00     0.02
  2   0.0001     -3.46    -0.02      -0.17    -0.00
  3   0.0002     -7.12    -0.13      -0.27     0.04
  4   0.0025    -82.55    -0.04      -3.37    -0.05
  5   0.0025    -84.23     0.31      -3.40    -0.00
  6   0.0868  -3003.22    -0.00    -181.08     0.11
  7   0.0869  -3008.61    -0.01    -181.73    -0.12
  8   0.2068  -6139.38    -0.04    -605.47     0.06
  9   0.2071  -6142.93     0.13    -606.46     0.06
 10   0.2098  -6182.64    -0.08    -617.83    -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.

08LD18    quality flag:1

Type:       CENTAURR  CENTAURR  CENTAURR

axisobj        39.660    43.401    38.682
ecceobj         0.296     0.429     0.241
incobj         14.607    14.942    14.500
qmin           27.808    24.367    29.336
qmax           52.438    64.944    48.819
amean          39.825    43.786    38.880
amin           39.477    43.264    38.682
amax           40.170    44.830    39.078
emean           0.300     0.435     0.245
emin            0.296     0.425     0.241
emax            0.305     0.449     0.249
imean          13.016    13.024    12.909
imin           12.999    12.678    12.897
imax           13.028    13.364    12.921
excite_mean     0.375     0.490     0.332
fracstop        0.000     0.004     0.000
cjmean          2.894     2.804     2.923

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       121.1     107.9     138.2
kozaiamp          0.6       5.3       0.2