Orbit Fit and Astrometric record for 17FQ161

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: 17FQ161   
# Created Tue Nov 30 02:14:03 2021
# Orbit generated from Bernstein formalism
# Fitting     12 observations of     12
# Arc:   2.03y
# First observation: 2017/03/26
#  Last observation: 2019/04/05
Preliminary a, adot, b, bdot, g, gdot:
   0.000011   0.012848  -0.000002  -0.001648   0.017785   0.000000
# Chi-squared of fit:    10.22 DOF:     18 RMS:  0.16
# Min/Max residuals:    -0.28    0.38
# Exact a, adot, b, bdot, g, gdot:
  1.144750E-05  1.290959E-02 -2.845647E-06 -1.655924E-03  1.779936E-02  2.494281E-03
# Covariance matrix:
  6.7028E-13 -2.6260E-12 -4.5282E-14  3.1790E-13  9.0150E-13 -1.0161E-10
 -2.6260E-12  1.5814E-11  3.0018E-13 -2.0472E-12 -3.9499E-12  6.5296E-10
 -4.5282E-14  3.0018E-13  2.3695E-13 -1.9864E-13 -6.3305E-14  1.2663E-11
  3.1790E-13 -2.0472E-12 -1.9864E-13  5.0352E-13  4.8338E-13 -8.6029E-11
  9.0150E-13 -3.9499E-12 -6.3305E-14  4.8338E-13  2.5707E-12 -1.5539E-10
 -1.0161E-10  6.5296E-10  1.2663E-11 -8.6029E-11 -1.5539E-10  2.7431E-08
#      lat0       lon0       xBary       yBary       zBary        JD0
    3.911644 -176.591907   -0.031072    0.067945   -0.991273  2457838.655271
# Heliocentric elements and errors
Epoch:              2457830.5000  =  2017/03/18
Mean Anomaly:          125.83541 +/-     2.125
Argument of Peri:        5.95006 +/-     1.848
Long of Asc Node:       31.15762 +/-     0.007
Inclination:             8.21989 +/-     0.002
Eccentricity:         0.26582097 +/-    0.0051
Semi-Major Axis:     47.95078015 +/-    0.1777
Time of Perihelion: 2415437.6810 +/-     675.9
Perihelion:          35.20445724 +/-    0.2760
Aphelion:            60.69710306 +/-    0.3313
Period (y)              332.0486 +/-      1.85
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -56.94489162 +/-    0.0050
Ecliptic Y           -3.42730486 +/-    0.0003
Ecliptic Z            3.83243971 +/-    0.0003
Ecliptic XDOT        -0.00027790 +/-    0.0000
Ecliptic YDOT        -0.00201257 +/-    0.0000
Ecliptic ZDOT        -0.00022802 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   57.17652223 +/-    0.0050
Geocenter to KBO     56.18180427 +/-    0.0051
# Hcoef:  6.13

The following table shows the complete astrometric record for 17FQ161. 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 (17FQ161) followed by the observatory code and reference code for the source of the astrometry.

2017 03  26.15447  12 18 43.502  +02 14 05.77  23.7r 17FQ161   807  C~2b81      
2017 03  26.26397  12 18 43.117  +02 14 07.69  23.7r 17FQ161   807  C~2b81      
2017 04  20.19005  12 17 20.234  +02 22 12.80        17FQ161   G37  C~2b81      
2017 04  20.27151  12 17 19.985  +02 22 14.34        17FQ161   G37  C~2b81      
2017 04  24.04811  12 17 08.599  +02 23 16.52  23.5r 17FQ161   304  C~2b81      
2017 04  25.09221  12 17 05.550  +02 23 33.15        17FQ161   304  C~2b81      
2018 03  11.21626  12 22 09.163  +01 45 45.87  23.6r 17FQ161   304  C~2b81      
2018 03  11.28622  12 22 08.926  +01 45 47.40        17FQ161   304  C~2b81      
2018 03  12.20193  12 22 05.891  +01 46 07.07        17FQ161   304  C~2b81      
2018 03  12.27824  12 22 05.642  +01 46 09.02        17FQ161   304  C~2b81      
2019 04  05.204040 12 23 17.887  +01 31 48.52  23.3G 17FQ161   G37  C~34cJ      
2019 04  05.275270 12 23 17.618  +01 31 49.86        17FQ161   G37  C~34cJ      

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     0.00       0.00     0.28
     2   0.0003     -6.06     0.16      -0.53    -0.10
     3   0.0685  -1338.80    -0.14     -48.84    -0.25
     4   0.0688  -1342.84    -0.12     -48.91    -0.07
     5   0.0791  -1524.15    -0.06     -59.61     0.05
     6   0.0820  -1572.70     0.20     -62.50     0.38
     7   0.9584   3505.09     0.03    -333.88    -0.16
     8   0.9586   3501.22    -0.00    -333.89    -0.15
     9   0.9611   3451.63    -0.07    -333.95    -0.28
    10   0.9613   3447.43    -0.07    -333.65     0.05
    11   2.0261   4784.16     0.17    -692.17     0.24
    12   2.0263   4779.93    -0.11    -692.54     0.00

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.

17FQ161    quality flag:2

Type:           2:1E  SCATNEAR  SCATNEAR

axisobj        47.599    48.158    47.129
ecceobj         0.275     0.290     0.264
incobj          8.269     8.267     8.272
qmin           33.836    32.183    33.658
qmax           62.295    65.270    63.785
amean          47.797    48.011    48.209
amin           47.286    46.703    46.821
amax           48.437    49.109    49.016
emean           0.271     0.295     0.265
emin            0.248     0.258     0.232
emax            0.290     0.333     0.304
imean           7.433     5.996     6.088
imin            6.506     2.614     4.137
imax            8.467     9.310     8.204
excite_mean     0.300     0.316     0.286
fracstop        1.000     1.000     1.000
cjmean          3.035     3.024     3.048

libcent 0       283.3    -180.0    -180.0
libamp  0        27.5    -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       207.6     180.4     176.7
kozaiamp        180.0     180.0     180.0