Orbit Fit and Astrometric record for 17DF168

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: 17DF168   
# Created Wed Jul 17 01:11:32 2024
# Orbit generated from Bernstein formalism
# Fitting     10 observations of     10
# Arc:   2.15d
# First observation: 2017/02/21
#  Last observation: 2017/02/23
# WARNING Fitting with energy constraint
# WARNING and with gdot fixed = 0
# WARNING MRQMIN stopped after  13 iterations -- oscilliatory solution
# Chi-squared of fit:     9.21 DOF:     16 RMS:  0.17
# Min/Max residuals:    -0.31    0.30
# Exact a, adot, b, bdot, g, gdot:
  1.569682E-05  2.383616E-02 -3.960112E-07  8.580880E-04  2.423845E-02  0.000000E+00
# Covariance matrix:
  3.7655E-11  5.7183E-08 -2.0027E-12 -3.1426E-09  1.1144E-08  0.0000E+00
  5.7183E-08  8.7559E-05 -3.0636E-09 -4.8073E-06  1.7048E-05  0.0000E+00
 -2.0027E-12 -3.0636E-09  3.5279E-13  1.2523E-10 -5.9660E-10  0.0000E+00
 -3.1426E-09 -4.8073E-06  1.2523E-10  2.8272E-07 -9.3617E-07  0.0000E+00
  1.1144E-08  1.7048E-05 -5.9660E-10 -9.3617E-07  3.3198E-06  0.0000E+00
  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  0.0000E+00  1.8739E-04
#      lat0       lon0       xBary       yBary       zBary        JD0
    4.341670 -170.796846    0.590462    0.060146   -0.790147  2457806.006401
# Heliocentric elements and errors
Epoch:              2457800.5000  =  2017/02/16
Mean Anomaly:          339.12982 +/-    67.128
Argument of Peri:       86.16314 +/-   127.178
Long of Asc Node:      124.87230 +/-    22.261
Inclination:             4.75569 +/-     0.920
Eccentricity:         0.03981773 +/-    0.5772
Semi-Major Axis:     43.67061374 +/-   22.9681
Time of Perihelion: 2463911.4111 +/-  230425.2
Perihelion:          41.93174902 +/-   33.4916
Aphelion:            45.40947846 +/-   34.7233
Period (y)              288.5972 +/-    227.68
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -41.48861788 +/-    3.0527
Ecliptic Y           -6.12828516 +/-    0.4944
Ecliptic Z            3.12328029 +/-    0.2348
Ecliptic XDOT         0.00044099 +/-    0.0015
Ecliptic YDOT        -0.00266324 +/-    0.0009
Ecliptic ZDOT         0.00009658 +/-    0.0001
# Distances at JD0 (AU)
Heliocenter to KBO   42.05491853 +/-    3.0125
Geocenter to KBO     41.25676283 +/-    3.1013
# Hcoef:  9.02

The following table shows the complete astrometric record for 17DF168. 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 (17DF168) followed by the observatory code and reference code for the source of the astrometry.

2017 02  21.50560  12 40 38.90   +00 20 41.9   24.7z 17DF168   T09  C~86uz      
2017 02  21.54193  12 40 38.78   +00 20 42.5   25.0z 17DF168   T09  C~86uz      
2017 02  21.56347  12 40 38.70   +00 20 43.1   24.5z 17DF168   T09  C~86uz      
2017 02  21.59307  12 40 38.59   +00 20 44.2   25.1z 17DF168   T09  C~86uz      
2017 02  21.59574  12 40 38.59   +00 20 43.9   25.2z 17DF168   T09  C~86uz      
2017 02  23.55566  12 40 32.00   +00 21 35.8   25.3r 17DF168   T09  C~86uz      
2017 02  23.57824  12 40 31.92   +00 21 36.5   25.7r 17DF168   T09  C~86uz      
2017 02  23.61010  12 40 31.79   +00 21 36.8   25.3r 17DF168   T09  C~86uz      
2017 02  23.62285  12 40 31.76   +00 21 37.2   25.5r 17DF168   T09  C~86uz      
2017 02  23.65247  12 40 31.63   +00 21 38.3   25.2r 17DF168   T09  C~86uz      

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    -0.03       0.00     0.20
     2   0.0001     -1.89     0.15      -0.15    -0.10
     3   0.0002     -3.23     0.04      -0.07    -0.11
     4   0.0002     -5.18    -0.22       0.29     0.14
     5   0.0002     -5.06     0.05       0.01    -0.15
     6   0.0056   -116.35     0.09       8.93     0.22
     7   0.0057   -117.73     0.04       9.10     0.30
     8   0.0058   -119.64     0.00       8.61    -0.31
     9   0.0058   -120.21     0.18       8.81    -0.16
    10   0.0059   -122.44    -0.31       9.05    -0.03

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.