Orbit Fit and Astrometric record for 20161

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: 20161     
# Created Thu Oct 19 01:36:17 2017
# Orbit generated by ELGB
# -->Covariance matrix from a Bernstein fit
# Fitting   24 observations of   24
# Arc:  12.04y
# First observation: 1996/10/08
#  Last observation: 2008/10/23
# Chi-squared of fit:   223.92 DOF:   42 RMS:  0.54
# Min/Max residuals:    -1.21    1.10
# Exact a, adot, b, bdot, g, gdot:
  2.617190E-05  3.189607E-02  1.683789E-06  6.589563E-03  2.894561E-02  1.057127E-02
# Covariance matrix:
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00
#      lat0       lon0       xBary       yBary       zBary        JD0
    4.307474    2.095755   -0.236077    0.072478   -0.964261  2450364.837050
# Heliocentric elements and errors
Epoch:              2450364.5000  =  1996/10/08
Mean Anomaly:           31.64811 +/-     0.000
Argument of Peri:      309.88227 +/-     0.000
Long of Asc Node:      343.00219 +/-     0.000
Inclination:            12.39760 +/-     0.000
Eccentricity:         0.40304674 +/-    0.0000
Semi-Major Axis:     48.24916157 +/-    0.0000
Time of Perihelion: 2439602.8621 +/-       0.0
Perihelion:          28.80249431 +/-    0.0000
Aphelion:            67.69582883 +/-    0.0000
Period (y)              335.1528 +/-      0.00
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X           35.39022471 +/-    0.0000
Ecliptic Y            1.52551014 +/-    0.0000
Ecliptic Z            2.59490784 +/-    0.0000
Ecliptic XDOT         0.00084593 +/-    0.0000
Ecliptic YDOT         0.00305435 +/-    0.0000
Ecliptic ZDOT         0.00069644 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   35.51780199 +/-    0.0000
Geocenter to KBO     34.54739964 +/-    0.0000
# Hcoef:  7.49

The following table shows the complete astrometric record for 20161. 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 (20161) followed by the observatory code and reference code for the source of the astrometry.

1996 10  08.33633  00 00 49.41   +04 47 05.9   23.0R 20161     568  C30144      
1996 10  08.38892  00 00 49.20   +04 47 04.5         20161     568  C30144      
1996 10  08.54487  00 00 48.38   +04 47 00.1         20161     568  C30144      
1996 10  12.39995  00 00 29.25   +04 45 02.0         20161     568  C30144      
1996 10  12.44652  00 00 29.01   +04 45 00.4         20161     568  C30144      
1996 10  12.51030  00 00 28.71   +04 44 58.7         20161     568  C30144      
1997 09  05.27890  00 09 45.96   +06 06 53.3         20161     675  Ca0009      
1997 09  05.45828  00 09 45.05   +06 06 48.8         20161     675  Ca0010      
1997 09  06.31941  00 09 40.84   +06 06 27.7   22.5R 20161     675  Ca0010      
1997 09  06.49878  00 09 39.94   +06 06 23.3   22.8R 20161     675  Ca0010      
1998 11  15.31809  00 10 15.40   +06 35 33.5   22.6R 20161     568  Ca3327      
1998 11  15.33171  00 10 15.35   +06 35 33.0   22.6R 20161     568  Ca3327      
1998 11  22.33160  00 09 56.75   +06 33 06.2   22.6R 20161     568  Ca3327      
1998 11  23.27500  00 09 54.61   +06 32 48.4   22.6R 20161     568  Ca3328      
1998 11  24.09341  00 09 52.84   +06 32 33.5   23.1R 20161     711  Ca3585      
1998 11  24.21661  00 09 52.51   +06 32 31.6   23.1R 20161     711  Ca3585      
1998 11  25.09750  00 09 50.63   +06 32 15.3   22.8R 20161     711  Ca3586      
1998 11  25.18707  00 09 50.44   +06 32 13.6   23.1R 20161     711  Ca3586      
2000 11  26.15906  00 21 19.50   +08 30 42.7   22.8R 20161     695  Cc3488      
2000 11  26.27921  00 21 19.22   +08 30 40.6   22.9R 20161     695  Cc3488      
2000 11  27.20699  00 21 17.21   +08 30 22.7   22.5R 20161     695  Cc3488      
2000 11  27.28647  00 21 17.07   +08 30 21.1   22.5R 20161     695  Cc3488      
2008 10  23.35209  01 06 23.49   +15 43 20.7   23.5r 20161     695  C~0gQ7      
2008 10  23.41422  01 06 23.19   +15 43 18.7   24.0r 20161     695  C~0gQ7      

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    -0.20       0.00    -1.21
  2   0.0001      0.00    -0.85       0.00    -0.11
  3   0.0006      0.00    -1.13       0.00     0.32
  4   0.0111      0.00     0.20       0.00     0.77
  5   0.0113      0.00     0.10       0.00     0.60
  6   0.0114      0.00     0.38       0.00     0.85
  7   0.9088      0.00     0.81       0.00    -0.60
  8   0.9093      0.00     0.52       0.00    -0.69
  9   0.9117      0.00     0.47       0.00    -0.48
 10   0.9121      0.00     0.42       0.00    -0.40
 11   2.1026      0.00     0.89       0.00    -0.19
 12   2.1027      0.00     0.77       0.00    -0.38
 13   2.1218      0.00     0.33       0.00    -0.21
 14   2.1244      0.00     0.58       0.00    -0.04
 15   2.1266      0.00     1.10       0.00     0.32
 16   2.1270      0.00     0.30       0.00     0.69
 17   2.1294      0.00    -0.08       0.00     0.31
 18   2.1296      0.00    -0.03       0.00     0.21
 19   4.1337      0.00    -0.52       0.00    -0.33
 20   4.1340      0.00    -0.61       0.00    -0.07
 21   4.1365      0.00    -0.84       0.00    -0.07
 22   4.1368      0.00    -0.34       0.00    -0.15
 23  12.0411      0.00     0.02       0.00     0.28
 24  12.0413      0.00     0.09       0.00     0.09

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.

20161    quality flag:3

Type:           2:1E      2:1E      2:1E
Type:         6:3EII    6:3EII    6:3EII

axisobj        48.243    48.244    48.243
ecceobj         0.400     0.400     0.400
incobj         12.406    12.406    12.406
qmin           28.181    28.180    28.182
qmax           68.383    68.439    68.355
amean          47.796    47.796    47.796
amin           47.266    47.264    47.279
amax           48.526    48.527    48.525
emean           0.380     0.380     0.380
emin            0.337     0.337     0.337
emax            0.410     0.411     0.410
imean          15.135    15.135    15.136
imin           13.190    13.180    13.201
imax           17.936    17.944    17.927
excite_mean     0.462     0.462     0.462
fracstop        1.000     1.000     1.000
cjmean          2.878     2.878     2.878

libcent 0        67.1      67.0      67.2
libamp  0        17.9      18.0      18.1
libcent 1       125.4     125.3     125.6
libamp  1       112.7     113.4     111.6
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       326.2     326.2     326.2
kozaiamp         33.4      33.5      33.3