Orbit Fit and Astrometric record for 18AZ18

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: 18AZ18    
# Created Tue Dec  7 02:14:12 2021
# Orbit generated from Bernstein formalism
# Fitting      7 observations of      7
# Arc:   1.87y
# First observation: 2018/01/15
#  Last observation: 2019/11/30
Preliminary a, adot, b, bdot, g, gdot:
  -0.000001   0.010571   0.000000  -0.001160   0.015374   0.000000
# Chi-squared of fit:     1.81 DOF:      8 RMS:  0.09
# Min/Max residuals:    -0.22    0.13
# Exact a, adot, b, bdot, g, gdot:
  1.038068E-05  1.045153E-02 -6.948370E-07 -1.150967E-03  1.542652E-02 -2.173016E-03
# Covariance matrix:
  7.7588E-13 -7.0395E-12 -1.3736E-15  4.2505E-13  5.4874E-12 -1.3453E-10
 -7.0395E-12  7.7093E-10 -1.4444E-12 -4.7028E-11 -7.4527E-10  1.4131E-08
 -1.3736E-15 -1.4444E-12  5.6860E-13 -2.9924E-13  1.4824E-12 -2.5363E-11
  4.2505E-13 -4.7028E-11 -2.9924E-13  3.2903E-12  4.5371E-11 -8.6403E-10
  5.4874E-12 -7.4527E-10  1.4824E-12  4.5371E-11  7.2671E-10 -1.3591E-08
 -1.3453E-10  1.4131E-08 -2.5363E-11 -8.6403E-10 -1.3591E-08  2.6018E-07
#      lat0       lon0       xBary       yBary       zBary        JD0
  -14.961666   84.086445   -0.504529   -0.219354   -0.821437  2458133.974801
# Heliocentric elements and errors
Epoch:              2458130.5000  =  2018/01/12
Mean Anomaly:          235.37898 +/-     5.487
Argument of Peri:       33.79122 +/-     5.320
Long of Asc Node:      197.54771 +/-     0.018
Inclination:            15.98446 +/-     0.002
Eccentricity:         0.27790415 +/-    0.0265
Semi-Major Axis:     54.74703168 +/-    0.2530
Time of Perihelion: 2509349.1453 +/-    2226.8
Perihelion:          39.53260449 +/-    1.4621
Aphelion:            69.96145887 +/-    1.4862
Period (y)              405.0877 +/-      2.81
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X            6.03557191 +/-    0.0113
Ecliptic Y           63.18411154 +/-    0.1089
Ecliptic Z          -16.73572425 +/-    0.0292
Ecliptic XDOT        -0.00188290 +/-    0.0000
Ecliptic YDOT        -0.00023687 +/-    0.0001
Ecliptic ZDOT        -0.00009792 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   65.64102792 +/-    0.1050
Geocenter to KBO     64.82343801 +/-    0.1133
# Hcoef:  7.67

The following table shows the complete astrometric record for 18AZ18. 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 (18AZ18) followed by the observatory code and reference code for the source of the astrometry.

2018 01  15.47400  05 36 54.253  +08 21 33.04  25.6R 18AZ18    568  C~31M1      
2018 01  16.47556  05 36 51.412  +08 21 38.33  25.6R 18AZ18    568  C~31M1      
2018 12  10.21903  05 41 17.574  +08 18 42.72  25.7r 18AZ18    304  C~31M1      
2018 12  10.27046  05 41 17.390  +08 18 42.52  25.7r 18AZ18    304  C~31M1      
2018 12  12.23106  05 41 10.865  +08 18 34.79  25.8r 18AZ18    304  C~31M1      
2019 11  29.29731  05 44 20.391  +08 17 04.76  25.7r 18AZ18    304  C~3d0D      
2019 11  30.27743  05 44 17.301  +08 16 58.31  25.6r 18AZ18    304  C~3d0D      

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     0.07       0.00    -0.10
     2   0.0027    -41.91    -0.07       7.03     0.13
     3   0.9001   3898.60     0.05    -326.68     0.07
     4   0.9002   3895.87    -0.10    -326.77     0.09
     5   0.9056   3798.76     0.04    -330.75    -0.22
     6   1.8695   6608.33    -0.00    -526.98     0.04
     7   1.8722   6562.22     0.01    -531.74    -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.

18AZ18    quality flag:3

Type:       SCATNEAR  SCATNEAR  SCATNEAR

axisobj        55.189    56.553    54.912
ecceobj         0.267     0.353     0.241
incobj         15.919    15.912    15.923
qmin           38.890    34.940    40.307
qmax           71.884    79.169    69.800
amean          55.017    56.463    54.713
amin           54.465    55.807    54.199
amax           55.667    57.349    55.350
emean           0.277     0.364     0.250
emin            0.264     0.347     0.238
emax            0.292     0.380     0.262
imean          15.874    15.765    15.982
imin           15.407    14.819    15.648
imax           16.310    16.483    16.305
excite_mean     0.389     0.454     0.372
fracstop        1.000     1.000     1.000
cjmean          3.046     2.988     3.060

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       167.8     165.3     175.2
kozaiamp        179.9     179.9     180.0