Orbit Fit and Astrometric record for 21DM15

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: 21DM15    
# Created Wed Dec 25 02:11:12 2024
# Orbit generated from Bernstein formalism
# Fitting     16 observations of     16
# Arc:   3.09y
# First observation: 2018/11/03
#  Last observation: 2021/12/07
Preliminary a, adot, b, bdot, g, gdot:
   0.000060   0.021843  -0.000001   0.000845   0.022919   0.000000
# Chi-squared of fit:     4.29 DOF:     26 RMS:  0.09
# Min/Max residuals:    -0.19    0.17
# Exact a, adot, b, bdot, g, gdot:
  1.458422E-05  2.166513E-02  1.452579E-07  8.392008E-04  2.270099E-02 -1.649457E-04
# Covariance matrix:
  8.8225E-13  3.0401E-14 -3.1840E-15  1.1635E-14  5.1738E-13  4.4897E-12
  3.0401E-14  4.4140E-13 -6.6744E-15  1.8491E-14  4.3289E-13  7.0851E-12
 -3.1840E-15 -6.6744E-15  4.3703E-13 -1.7512E-13 -7.6151E-15 -1.3309E-13
  1.1635E-14  1.8491E-14 -1.7512E-13  8.9169E-14  2.3391E-14  3.7194E-13
  5.1738E-13  4.3289E-13 -7.6151E-15  2.3391E-14  7.4736E-13  8.9885E-12
  4.4897E-12  7.0851E-12 -1.3309E-13  3.7194E-13  8.9885E-12  1.4255E-10
#      lat0       lon0       xBary       yBary       zBary        JD0
   -0.936544  108.794548    0.923562   -0.005986   -0.374499  2458425.784105
# Heliocentric elements and errors
Epoch:              2458420.5000  =  2018/10/29
Mean Anomaly:          307.35932 +/-     0.409
Argument of Peri:       33.20031 +/-     0.466
Long of Asc Node:      130.48559 +/-     0.007
Inclination:             2.38749 +/-     0.001
Eccentricity:         0.03709300 +/-    0.0005
Semi-Major Axis:     45.40966806 +/-    0.0056
Time of Perihelion: 2474763.8051 +/-     126.9
Perihelion:          43.72528708 +/-    0.0226
Aphelion:            47.09404905 +/-    0.0227
Period (y)              306.0065 +/-      0.06
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -13.43689948 +/-    0.0005
Ecliptic Y           42.34118466 +/-    0.0016
Ecliptic Z           -0.72007502 +/-    0.0000
Ecliptic XDOT        -0.00246009 +/-    0.0000
Ecliptic YDOT        -0.00086150 +/-    0.0000
Ecliptic ZDOT         0.00010133 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   44.42797198 +/-    0.0015
Geocenter to KBO     44.05093585 +/-    0.0017
# Hcoef:  7.27

The following table shows the complete astrometric record for 21DM15. 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 (21DM15) followed by the observatory code and reference code for the source of the astrometry.

2018 11  03.283304 07 20 50.97   +21 11 37.1   24.0g 21DM15    W84  C~5zHK      
2019 03  01.132903 07 13 08.24   +21 26 30.9         21DM15    W84  C~5zHK      
2019 03  01.134981 07 13 08.25   +21 26 30.7         21DM15    W84  C~5zHK      
2020 01  03.249485 07 22 34.82   +21 10 51.9   23.4V 21DM15    W84  C~5zHK      
2020 01  03.251564 07 22 34.82   +21 10 51.9   23.5V 21DM15    W84  C~5zHK      
2021 02  17.22589  07 24 24.954  +21 10 45.84  23.8r 21DM15    568  C~5Jzg      
2021 02  17.40002  07 24 24.282  +21 10 47.42  23.6r 21DM15    568  C~5Jzg      
2021 03  09.03994  07 23 26.190  +21 13 11.42  23.9G 21DM15    304  C~5Jzg      
2021 03  09.09481  07 23 26.060  +21 13 11.89        21DM15    304  C~5Jzg      
2021 03  17.09111  07 23 11.657  +21 13 52.70  23.9r 21DM15    304  C~5Jzg      
2021 03  18.01487  07 23 10.373  +21 13 56.76  23.9r 21DM15    304  C~5Jzg      
2021 04  11.99946  07 23 06.386  +21 14 44.81  23.8r 21DM15    304  C~5Jzg      
2021 10  30.36559  07 36 44.173  +20 46 41.11  23.7r 21DM15    304  C~5Jzg      
2021 12  06.23741  07 35 19.896  +20 49 38.82  24.0r 21DM15    304  C~5Jzg      
2021 12  07.24533  07 35 16.107  +20 49 47.11  23.8r 21DM15    304  C~5Jzg      
2021 12  07.31260  07 35 15.849  +20 49 47.74  23.6r 21DM15    304  C~5Jzg      

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     0.10       0.00     0.09
     2   0.3227  -6529.55    -0.14      36.41     0.10
     3   0.3227  -6529.39     0.11      36.23    -0.08
     4   1.1662   1444.69    -0.14     156.84    -0.06
     5   1.1662   1444.69     0.01     156.84    -0.06
     6   2.2914   2970.63     0.03     368.97    -0.07
     7   2.2919   2961.10    -0.19     369.19    -0.05
     8   2.3457   2136.34    -0.01     396.16    -0.05
     9   2.3458   2134.47    -0.13     396.36     0.09
    10   2.3677   1929.32     0.17     408.31    -0.05
    11   2.3702   1910.97     0.15     409.79    -0.01
    12   2.4386   1849.00     0.03     449.50     0.01
    13   2.9900  13441.74    -0.02     521.16    -0.04
    14   3.0909  12242.16    -0.12     506.25     0.14
    15   3.0937  12188.21     0.06     505.94    -0.01
    16   3.0939  12184.53     0.09     505.98     0.05

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.

21DM15    quality flag:3

Type:      CLASSICAL CLASSICAL CLASSICAL

axisobj        45.875    45.888    45.862
ecceobj         0.038     0.039     0.038
incobj          2.390     2.389     2.389
qmin           43.083    43.116    43.125
qmax           48.221    48.464    48.400
amean          45.655    45.669    45.642
amin           45.309    45.310    45.279
amax           46.002    46.046    46.024
emean           0.038     0.039     0.038
emin            0.025     0.026     0.025
emax            0.050     0.053     0.052
imean           1.442     1.441     1.443
imin            1.008     1.008     1.009
imax            1.815     1.813     1.818
excite_mean     0.046     0.047     0.046
fracstop        1.000     1.000     1.000
cjmean          3.119     3.119     3.119

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       188.5     188.8     187.6
kozaiamp        180.0     180.0     179.9