Orbit Fit and Astrometric record for 16ER398

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: 16ER398   
# Created Tue Apr  1 01:10:45 2025
# Orbit generated from Bernstein formalism
# Fitting     24 observations of     24
# Arc:   3.08y
# First observation: 2016/02/08
#  Last observation: 2019/03/08
Preliminary a, adot, b, bdot, g, gdot:
  -0.000226   0.024112   0.000011  -0.002611   0.022667   0.000000
# Chi-squared of fit:    17.99 DOF:     42 RMS:  0.15
# Min/Max residuals:    -0.31    0.39
# Exact a, adot, b, bdot, g, gdot:
  1.520550E-05  2.380233E-02 -3.636865E-06 -2.603234E-03  2.332775E-02 -4.792179E-03
# Covariance matrix:
  3.3113E-13  1.0408E-12 -5.3512E-15 -1.1639E-13  8.5482E-13  1.6061E-11
  1.0408E-12  6.8046E-12 -2.1242E-14 -6.9621E-13  4.5218E-12  9.8152E-11
 -5.3512E-15 -2.1242E-14  1.1763E-13 -3.8766E-14 -2.0538E-14 -3.2620E-13
 -1.1639E-13 -6.9621E-13 -3.8766E-14  1.0224E-13 -4.8157E-13 -1.0136E-11
  8.5482E-13  4.5218E-12 -2.0538E-14 -4.8157E-13  3.4488E-12  6.6761E-11
  1.6061E-11  9.8152E-11 -3.2620E-13 -1.0136E-11  6.6761E-11  1.4257E-09
#      lat0       lon0       xBary       yBary       zBary        JD0
  -11.161368  139.374604    0.012701   -0.190420   -0.966045  2457426.923819
# Heliocentric elements and errors
Epoch:              2457420.5000  =  2016/02/02
Mean Anomaly:          330.05948 +/-     0.092
Argument of Peri:      294.43456 +/-     0.217
Long of Asc Node:      259.20501 +/-     0.002
Inclination:            12.53073 +/-     0.000
Eccentricity:         0.29422844 +/-    0.0015
Semi-Major Axis:     56.35262313 +/-    0.0601
Time of Perihelion: 2470271.1914 +/-      33.7
Perihelion:          39.77207901 +/-    0.0954
Aphelion:            72.93316725 +/-    0.1156
Period (y)              423.0380 +/-      0.68
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -32.66345547 +/-    0.0025
Ecliptic Y           28.03206964 +/-    0.0022
Ecliptic Z           -8.29814103 +/-    0.0007
Ecliptic XDOT        -0.00135565 +/-    0.0000
Ecliptic YDOT        -0.00252502 +/-    0.0000
Ecliptic ZDOT        -0.00019086 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   43.83557227 +/-    0.0024
Geocenter to KBO     42.86740716 +/-    0.0034
# Hcoef:  8.51

The following table shows the complete astrometric record for 16ER398. 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 (16ER398) followed by the observatory code and reference code for the source of the astrometry.

2016 02  08.42303  09 13 15.67   +04 23 14.4   24.7r 16ER398   T09  C~8eUr      
2016 02  08.44625  09 13 15.53   +04 23 14.5   24.9r 16ER398   T09  C~8eUr      
2016 02  08.47058  09 13 15.43   +04 23 15.0   25.0r 16ER398   T09  C~8eUr      
2016 02  08.47270  09 13 15.42   +04 23 14.9   25.2r 16ER398   T09  C~8eUr      
2016 03  04.34374  09 11 28.75   +04 32 25.6   24.3i 16ER398   T09  C~8eUr      
2016 03  04.37256  09 11 28.62   +04 32 25.9   24.4i 16ER398   T09  C~8eUr      
2016 03  04.38622  09 11 28.58   +04 32 26.3   24.3i 16ER398   T09  C~8eUr      
2016 03  07.35383  09 11 17.25   +04 33 36.9   25.6g 16ER398   T09  C~8eUr      
2016 03  07.37297  09 11 17.17   +04 33 37.7   25.8g 16ER398   T09  C~8eUr      
2016 03  07.40429  09 11 17.05   +04 33 38.4   25.4g 16ER398   T09  C~8eUr      
2016 03  12.30519  09 10 59.34   +04 35 34.9   24.8z 16ER398   T09  C~8eUr      
2016 03  12.32109  09 10 59.27   +04 35 35.4   24.5z 16ER398   T09  C~8eUr      
2016 03  12.33760  09 10 59.22   +04 35 35.7   24.1z 16ER398   T09  C~8eUr      
2018 11  15.53970  09 32 16.86   +02 40 56.8   24.8z 16ER398   T09  C~8eUr      
2018 11  15.55104  09 32 16.88   +02 40 56.4   24.2z 16ER398   T09  C~8eUr      
2018 11  15.58818  09 32 16.90   +02 40 55.9   24.2z 16ER398   T09  C~8eUr      
2018 11  15.61442  09 32 16.91   +02 40 55.3   24.9z 16ER398   T09  C~8eUr      
2019 01  06.45393  09 30 50.80   +02 33 52.2   26.0g 16ER398   T09  C~8eUr      
2019 01  06.58489  09 30 50.34   +02 33 52.8   25.4g 16ER398   T09  C~8eUr      
2019 01  06.59550  09 30 50.33   +02 33 53.2   25.8g 16ER398   T09  C~8eUr      
2019 01  06.61703  09 30 50.23   +02 33 53.2   25.5g 16ER398   T09  C~8eUr      
2019 03  08.29181  09 26 31.03   +02 52 05.6   24.9r 16ER398   T09  C~8eUr      
2019 03  08.29390  09 26 31.03   +02 52 05.6   24.8r 16ER398   T09  C~8eUr      
2019 03  08.31288  09 26 30.92   +02 52 06.1   25.0r 16ER398   T09  C~8eUr      

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     0.19       0.00     0.39
     2   0.0001     -2.03    -0.17      -0.54    -0.10
     3   0.0001     -3.60    -0.01      -0.52    -0.03
     4   0.0001     -3.71     0.03      -0.66    -0.16
     5   0.0682  -1690.80     0.06      41.69     0.13
     6   0.0683  -1692.74    -0.05      41.39    -0.31
     7   0.0683  -1693.43     0.13      41.59    -0.17
     8   0.0765  -1876.28     0.09      57.69    -0.09
     9   0.0765  -1877.66    -0.11      58.09     0.21
    10   0.0766  -1879.58    -0.10      58.22     0.16
    11   0.0900  -2167.23     0.08      89.28    -0.03
    12   0.0901  -2168.38    -0.15      89.44     0.02
    13   0.0901  -2169.19     0.01      89.50    -0.03
    14   2.7683  18189.83    -0.18    -627.80    -0.05
    15   2.7683  18190.24     0.07    -628.08    -0.13
    16   2.7684  18190.68     0.00    -628.47     0.15
    17   2.7685  18191.01    -0.02    -629.00     0.10
    18   2.9104  17085.42    -0.29   -1431.01    -0.13
    19   2.9108  17078.63     0.03   -1432.56    -0.19
    20   2.9108  17078.36     0.33   -1432.22     0.27
    21   2.9109  17076.92     0.07   -1432.68     0.05
    22   3.0770  13023.78     0.07   -1583.63     0.03
    23   3.0770  13023.78     0.21   -1583.63     0.02
    24   3.0770  13022.05    -0.29   -1583.66    -0.12

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.

16ER398    quality flag:3

Type:       SCATNEAR  SCATNEAR  SCATNEAR

axisobj        55.858    55.999    55.721
ecceobj         0.286     0.290     0.282
incobj         12.506    12.506    12.507
qmin           39.125    38.987    39.250
qmax           73.560    74.068    73.166
amean          55.915    56.066    55.765
amin           55.331    55.486    55.168
amax           56.617    56.806    56.480
emean           0.285     0.289     0.281
emin            0.272     0.277     0.266
emax            0.299     0.304     0.295
imean          14.257    14.227    14.256
imin           13.750    13.745    13.783
imax           14.605    14.608    14.659
excite_mean     0.376     0.379     0.373
fracstop        1.000     1.000     1.000
cjmean          3.071     3.070     3.072

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       181.7     186.7     173.4
kozaiamp        180.0     179.9     180.0