Orbit Fit and Astrometric record for 18AH39

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: 18AH39    
# Created Fri Apr 19 01:18:25 2024
# Orbit generated from Bernstein formalism
# Fitting      9 observations of      9
# Arc:   1.87y
# First observation: 2018/01/15
#  Last observation: 2019/12/01
Preliminary a, adot, b, bdot, g, gdot:
   0.000030   0.010499   0.000009   0.005369   0.016123   0.000000
# Chi-squared of fit:     2.86 DOF:     12 RMS:  0.10
# Min/Max residuals:    -0.17    0.25
# Exact a, adot, b, bdot, g, gdot:
  9.954775E-06  1.059810E-02  5.350294E-06  5.410420E-03  1.621558E-02  1.541388E-03
# Covariance matrix:
  7.1367E-13 -9.3499E-13  5.1455E-14 -2.1612E-13 -4.1049E-13 -2.2428E-11
 -9.3499E-13  2.5553E-12 -1.6839E-13  6.5800E-13  2.4600E-13  7.2478E-11
  5.1455E-14 -1.6839E-13  5.4265E-13 -4.5180E-13 -8.2299E-14 -6.4342E-12
 -2.1612E-13  6.5800E-13 -4.5180E-13  6.7367E-13  4.3238E-13  2.6403E-11
 -4.1049E-13  2.4600E-13 -8.2299E-14  4.3238E-13  2.5886E-12  3.7486E-11
 -2.2428E-11  7.2478E-11 -6.4342E-12  2.6403E-11  3.7486E-11  2.7929E-09
#      lat0       lon0       xBary       yBary       zBary        JD0
   11.747476  117.245827    0.040275    0.201256   -0.967089  2458134.110811
# Heliocentric elements and errors
Epoch:              2458130.5000  =  2018/01/12
Mean Anomaly:          130.61771 +/-     1.050
Argument of Peri:      239.92946 +/-     0.995
Long of Asc Node:       95.85525 +/-     0.003
Inclination:            29.33049 +/-     0.003
Eccentricity:         0.18123962 +/-    0.0021
Semi-Major Axis:     55.23627250 +/-    0.0526
Time of Perihelion: 2403726.0375 +/-     430.3
Perihelion:          45.22527137 +/-    0.1257
Aphelion:            65.24727363 +/-    0.1334
Period (y)              410.5299 +/-      0.59
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -28.05998199 +/-    0.0028
Ecliptic Y           54.56866824 +/-    0.0053
Ecliptic Z           12.55604213 +/-    0.0012
Ecliptic XDOT        -0.00161640 +/-    0.0000
Ecliptic YDOT        -0.00076294 +/-    0.0000
Ecliptic ZDOT         0.00094721 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   62.63191148 +/-    0.0048
Geocenter to KBO     61.66910008 +/-    0.0061
# Hcoef:  7.12

The following table shows the complete astrometric record for 18AH39. 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 (18AH39) followed by the observatory code and reference code for the source of the astrometry.

2018 01  15.61001  08 07 57.297  +32 12 38.64  24.7r 18AH39    568  C~4ZY2      
2018 01  16.60555  08 07 53.322  +32 12 53.31  24.8r 18AH39    568  C~4ZY2      
2018 12  09.34013  08 13 15.256  +32 11 44.94  25.1r 18AH39    304  C~4ZY2      
2018 12  10.33679  08 13 12.490  +32 12 04.11  25.1r 18AH39    304  C~4ZY2      
2018 12  11.29370  08 13 09.805  +32 12 22.37  25.2r 18AH39    304  C~4ZY2      
2018 12  11.32868  08 13 09.717  +32 12 22.94  25.1r 18AH39    304  C~4ZY2      
2019 02  02.18719  08 09 55.423  +32 26 38.64  25.2r 18AH39    304  C~4ZY2      
2019 11  29.31925  08 16 45.254  +32 18 06.85  25.0r 18AH39    304  C~4ZY2      
2019 12  01.33258  08 16 40.995  +32 18 45.42  25.0r 18AH39    304  C~4ZY2      

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     0.08       0.00    -0.02
     2   0.0027    -52.42    -0.08       3.47     0.04
     3   0.8973   3948.02     0.25     840.61    -0.03
     4   0.9000   3909.46    -0.10     851.30    -0.01
     5   0.9026   3872.12    -0.17     861.34    -0.06
     6   0.9027   3870.90     0.01     861.64    -0.12
     7   1.0474   1278.78     0.02    1145.53     0.20
     8   1.8692   6453.33    -0.04    1828.73     0.00
     9   1.8747   6391.72     0.04    1853.53    -0.01

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.

18AH39    quality flag:2

Type:       SCATNEAR  SCATNEAR  SCATEXTD

axisobj        55.533    55.702    55.376
ecceobj         0.183     0.189     0.178
incobj         29.207    29.205    29.209
qmin           43.690    43.941    44.573
qmax           67.899    67.808    66.351
amean          55.422    55.506    55.224
amin           54.852    54.851    54.721
amax           56.134    56.165    55.816
emean           0.183     0.183     0.175
emin            0.152     0.154     0.161
emax            0.210     0.207     0.189
imean          27.709    27.767    27.719
imin           27.279    27.386    27.475
imax           28.259    28.275    27.994
excite_mean     0.500     0.501     0.497
fracstop        1.000     1.000     1.000
cjmean          2.906     2.905     2.907

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       179.2     178.0     203.1
kozaiamp        179.9     180.0     179.9