Orbit Fit and Astrometric record for 18AG37

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: 18AG37    
# Created Fri Mar 29 01:19:02 2024
# Orbit generated from Bernstein formalism
# Fitting     11 observations of     11
# Arc:   2.03y
# First observation: 2018/01/15
#  Last observation: 2020/01/25
Preliminary a, adot, b, bdot, g, gdot:
  -0.000007   0.002403  -0.000001   0.000476   0.007566   0.000000
# WARNING Fitting with energy constraint
# WARNING MRQMIN stopped after  13 iterations -- oscilliatory solution
# Chi-squared of fit:     5.31 DOF:     17 RMS:  0.12
# Min/Max residuals:    -0.22    0.22
# Exact a, adot, b, bdot, g, gdot:
  4.554534E-06  2.403313E-03  7.902823E-07  4.748565E-04  7.593712E-03 -3.529808E-04
# Covariance matrix:
  4.7677E-13 -9.1090E-12  2.7953E-13 -1.8739E-12 -2.2011E-11 -1.9486E-09
 -9.1090E-12 -3.5073E-10  1.0476E-11 -7.5310E-11 -8.9416E-10 -7.7961E-08
  2.7953E-13  1.0476E-11  2.5686E-13  1.8576E-12  2.6710E-11  2.3244E-09
 -1.8739E-12 -7.5310E-11  1.8576E-12 -1.5805E-11 -1.9181E-10 -1.6723E-08
 -2.2011E-11 -8.9416E-10  2.6710E-11 -1.9181E-10 -2.2770E-09 -1.9857E-07
 -1.9486E-09 -7.7961E-08  2.3244E-09 -1.6723E-08 -1.9857E-07 -1.7311E-05
#      lat0       lon0       xBary       yBary       zBary        JD0
   15.047990  120.521265    0.096208    0.255591   -0.950154  2458134.135972
# Heliocentric elements and errors
Epoch:              2458130.5000  =  2018/01/12
Mean Anomaly:          196.86490 +/-   315.152
Argument of Peri:      228.98477 +/-   228.985
Long of Asc Node:       68.30410 +/-    68.304
Inclination:            18.66260 +/-    18.663
Eccentricity:         0.65440122 +/-    0.6544
Semi-Major Axis:     80.67657551 +/-   80.6766
Time of Perihelion: 2578070.6317 +/- 9999999.9
Perihelion:          27.88172606 +/-   59.7050
Aphelion:           133.47142495 +/-  143.5337
Period (y)              724.6518 +/-   1086.98
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -65.00444573 +/-  -65.0044
Ecliptic Y          110.44119709 +/-  110.4412
Ecliptic Z           34.18994425 +/-   34.1899
Ecliptic XDOT        -0.00065548 +/-   -0.0007
Ecliptic YDOT        -0.00058913 +/-   -0.0006
Ecliptic ZDOT         0.00013215 +/-    0.0001
# Distances at JD0 (AU)
Heliocenter to KBO  132.63403887 +/-   97.7222
Geocenter to KBO    131.68789818 +/-  131.6879
# Hcoef:  4.16

The following table shows the complete astrometric record for 18AG37. 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 (18AG37) followed by the observatory code and reference code for the source of the astrometry.

2018 01  15.635171 08 26 28.009  +34 41 18.77  25.3G 18AG37    568  C~4ZXz      
2018 01  16.630635 08 26 25.988  +34 41 25.98  25.3G 18AG37    568  C~4ZXz      
2019 03  01.13333  08 25 43.165  +34 44 02.47  25.3r 18AG37    304  C~4ZXz      
2019 03  02.09349  08 25 41.587  +34 44 03.43  25.2r 18AG37    304  C~4ZXz      
2019 03  02.14413  08 25 41.512  +34 44 03.30  25.3r 18AG37    304  C~4ZXz      
2019 03  03.081253 08 25 40.01   +34 44 04.0   25.3r 18AG37    W84  C~4xVr      
2019 03  03.083106 08 25 40.01   +34 44 03.8   25.7g 18AG37    W84  C~4xVr      
2019 05  01.29827  08 24 58.399  +34 40 07.42  25.3r 18AG37    568  C~4ZXz      
2019 05  02.31035  08 24 58.743  +34 40 00.01  25.2r 18AG37    568  C~4ZXz      
2020 01  24.569616 08 27 32.247  +34 41 24.35  25.3G 18AG37    568  C~4ZXz      
2020 01  25.444963 08 27 30.456  +34 41 29.84  25.0G 18AG37    568  C~4ZXz      

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     0.09       0.00     0.04
     2   0.0027    -25.93    -0.02       0.87     0.02
     3   1.1211   -576.20    -0.00      23.37    -0.14
     4   1.1238   -595.30    -0.22      19.56     0.06
     5   1.1239   -596.16    -0.07      19.20    -0.07
     6   1.1265   -614.29    -0.07      15.37     0.09
     7   1.1265   -614.24     0.02      15.18    -0.09
     8   1.2886  -1054.60     0.11    -338.78    -0.18
     9   1.2914  -1048.69     0.12    -344.94     0.22
    10   2.0231    766.38     0.04     201.08     0.06
    11   2.0255    743.62     0.01     200.92     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.

18AG37    quality flag:3

Type:       CENTAURR  CENTAURR  CENTAURR

axisobj        80.735    80.766    80.703
ecceobj         0.652     0.651     0.652
incobj         18.482    18.481    18.482
qmin           26.843    27.003    26.861
qmax          137.710   139.400   141.002
amean          78.891    80.933    80.330
amin           76.231    77.576    76.113
amax           82.863    83.548    84.805
emean           0.648     0.655     0.655
emin            0.630     0.630     0.628
emax            0.663     0.669     0.669
imean          16.583    16.732    16.549
imin           15.782    15.592    15.630
imax           18.391    18.425    19.014
excite_mean     0.708     0.715     0.714
fracstop        0.183     0.187     0.183
cjmean          2.745     2.747     2.744

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       275.5     275.5     273.9
kozaiamp         45.9      46.3      47.4