Orbit Fit and Astrometric record for 18GT15

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: 18GT15    
# Created Wed Nov 27 02:10:53 2024
# Orbit generated from Bernstein formalism
# Fitting     10 observations of     10
# Arc:  32.21d
# First observation: 2018/04/12
#  Last observation: 2018/05/14
Preliminary a, adot, b, bdot, g, gdot:
   0.000000   0.018564   0.000001   0.007802   0.020152   0.000000
# WARNING MRQMIN stopped after  13 iterations -- oscilliatory solution
# WARNING Fitting with energy constraint
# Chi-squared of fit:     2.57 DOF:     15 RMS:  0.09
# Min/Max residuals:    -0.19    0.14
# Exact a, adot, b, bdot, g, gdot:
  1.309440E-05  1.627187E-02  7.266816E-06  7.928673E-03  1.971929E-02  1.926065E-03
# Covariance matrix:
  2.8771E-12  1.3725E-09  2.6111E-14 -3.7606E-11  3.3250E-10 -7.2031E-09
  1.3725E-09  7.9091E-07  2.6637E-11 -2.4784E-08  1.8503E-07 -8.3342E-06
  2.6111E-14  2.6637E-11  2.6843E-13 -4.5587E-12  5.2486E-12 -9.5733E-10
 -3.7606E-11 -2.4784E-08 -4.5587E-12  1.0036E-09 -5.5310E-09  4.4551E-07
  3.3250E-10  1.8503E-07  5.2486E-12 -5.5310E-09  4.3809E-08 -1.5952E-06
 -7.2031E-09 -8.3342E-06 -9.5733E-10  4.4551E-07 -1.5952E-06  3.3186E-04
#      lat0       lon0       xBary       yBary       zBary        JD0
   -1.214434  168.292443   -0.547594   -0.017595   -0.835160  2458220.577601
# Heliocentric elements and errors
Epoch:              2458220.5000  =  2018/04/12
Mean Anomaly:           38.00302 +/-   159.764
Argument of Peri:      306.02259 +/-   263.595
Long of Asc Node:      171.35821 +/-     0.165
Inclination:            26.00873 +/-     1.463
Eccentricity:         0.15989453 +/-    0.8271
Semi-Major Axis:     58.19641820 +/-   13.3706
Time of Perihelion: 2441102.2864 +/-   71722.4
Perihelion:          48.89112950 +/-   49.4276
Aphelion:            67.50170689 +/-   50.5710
Period (y)              443.9689 +/-    153.00
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -50.57599459 +/-    0.5269
Ecliptic Y            9.91399076 +/-    0.1093
Ecliptic Z           -1.07443527 +/-    0.0114
Ecliptic XDOT        -0.00073653 +/-    0.0025
Ecliptic YDOT        -0.00215754 +/-    0.0006
Ecliptic ZDOT         0.00109476 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   51.54971244 +/-    0.5174
Geocenter to KBO     50.71175263 +/-    0.5383
# Hcoef:  7.51

The following table shows the complete astrometric record for 18GT15. 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 (18GT15) followed by the observatory code and reference code for the source of the astrometry.

2018 04  12.07680  11 15 02.290  +03 30 42.05  24.5r 18GT15    807  C~3wrJ      
2018 04  13.08164  11 14 59.388  +03 31 06.32  24.6r 18GT15    807  C~3wrJ      
2018 04  14.11923  11 14 56.43   +03 31 31.2   24.5r 18GT15    309  C~5Mt7      
2018 04  14.12391  11 14 56.42   +03 31 31.2         18GT15    309  C~5Mt7      
2018 04  14.13327  11 14 56.39   +03 31 31.6         18GT15    309  C~5Mt7      
2018 04  14.13795  11 14 56.38   +03 31 31.7   24.7r 18GT15    309  C~5Mt7      
2018 05  14.23892  11 13 55.495  +03 40 58.46        18GT15    G37  C~3wrJ      
2018 05  14.24618  11 13 55.479  +03 40 58.35        18GT15    G37  C~3wrJ      
2018 05  14.27884  11 13 55.441  +03 40 58.94        18GT15    G37  C~3wrJ      
2018 05  14.28623  11 13 55.444  +03 40 58.83        18GT15    G37  C~3wrJ      

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    -0.01       0.00    -0.19
     2   0.0028    -49.47     0.03       5.39    -0.10
     3   0.0056    -99.96    -0.03      11.02     0.06
     4   0.0056   -100.10     0.06      10.96    -0.02
     5   0.0056   -100.67    -0.05      11.15     0.13
     6   0.0056   -100.84     0.00      11.19     0.14
     7   0.0881  -1161.20    -0.01     177.50     0.13
     8   0.0881  -1161.38    -0.03     177.31    -0.10
     9   0.0882  -1162.13    -0.10     177.63     0.04
    10   0.0882  -1162.05     0.14     177.54    -0.08

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.

18GT15    quality flag:0

Type:      ERR2LARGE ERR2LARGE ERR2LARGE

axisobj         0.000     0.000     0.000
ecceobj        -1.000    -1.000    -1.000
incobj         -1.000    -1.000    -1.000
qmin            0.000     0.000     0.000
qmax            0.000     0.000     0.000
amean           0.000     0.000     0.000
amin            0.000     0.000     0.000
amax            0.000     0.000     0.000
emean           0.000     0.000     0.000
emin            0.000     0.000     0.000
emax            0.000     0.000     0.000
imean           0.000     0.000     0.000
imin            0.000     0.000     0.000
imax            0.000     0.000     0.000
excite_mean     0.000     0.000     0.000
fracstop        0.000     0.000     0.000
cjmean          0.000     0.000     0.000

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         0.0       0.0       0.0
kozaiamp          0.0       0.0       0.0