Orbit Fit and Astrometric record for 15DA225

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: 15DA225   
# Created Mon Dec  6 02:13:12 2021
# Orbit generated by ELGB
# -->Covariance matrix from a Bernstein fit
# Fitting     15 observations of     15
# Arc:   5.90y
# First observation: 2015/02/18
#  Last observation: 2021/01/11
# Chi-squared of fit:    14.94 DOF:     24 RMS:  0.18
# Min/Max residuals:    -0.44    0.37
# Exact a, adot, b, bdot, g, gdot:
  1.718202E-05  3.028294E-02 -9.065963E-06 -1.585993E-02  2.756031E-02 -6.065218E-03
# Covariance matrix:
  2.8316E-13 -2.7460E-13 -2.7951E-14  8.7696E-14  3.2792E-13 -9.0267E-13
 -2.7460E-13  5.4786E-13  6.7988E-14 -2.1147E-13 -4.7987E-13  2.1789E-12
 -2.7951E-14  6.7988E-14  1.6424E-13 -6.0955E-14 -4.2055E-14  2.9608E-13
  8.7696E-14 -2.1147E-13 -6.0955E-14  1.0651E-13  1.3553E-13 -9.1687E-13
  3.2792E-13 -4.7987E-13 -4.2055E-14  1.3553E-13  1.1112E-12 -1.3907E-12
 -9.0267E-13  2.1789E-12  2.9608E-13 -9.1687E-13 -1.3907E-12  9.4520E-12
#      lat0       lon0       xBary       yBary       zBary        JD0
    0.906560  122.555684   -0.437114    0.014125   -0.883029  2457071.660548
# Heliocentric elements and errors
Epoch:              2457072.5000  =  2015/02/19
Mean Anomaly:          352.22526 +/-     0.007
Argument of Peri:      206.05988 +/-     0.019
Long of Asc Node:      304.92846 +/-     0.000
Inclination:            27.56561 +/-     0.000
Eccentricity:         0.51921085 +/-    0.0002
Semi-Major Axis:     74.22752618 +/-    0.0310
Time of Perihelion: 2462117.1291 +/-     143.2
Perihelion:          35.68778913 +/-    0.0195
Aphelion:           112.76726322 +/-    0.0487
Period (y)              639.5223 +/-      0.40
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -20.36991701 +/-    0.0007
Ecliptic Y           31.08829568 +/-    0.0012
Ecliptic Z            0.57374010 +/-    0.0000
Ecliptic XDOT        -0.00222849 +/-    0.0000
Ecliptic YDOT        -0.00211118 +/-    0.0000
Ecliptic ZDOT        -0.00158477 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   37.17194716 +/-    0.0011
Geocenter to KBO     36.28423052 +/-    0.0014
# Hcoef:  7.47

The following table shows the complete astrometric record for 15DA225. 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 (15DA225) followed by the observatory code and reference code for the source of the astrometry.

2015 02  18.15977  08 20 12.55   +20 28 18.9   22.5R 15DA225   695  C~1zPy      
2015 02  18.20668  08 20 12.31   +20 28 19.2         15DA225   695  C~1zPy      
2015 02  18.25255  08 20 12.06   +20 28 19.3         15DA225   695  C~1zPy      
2015 03  16.13648  08 18 22.44   +20 29 57.1   22.5R 15DA225   G37  C~1zPy      
2015 03  16.20489  08 18 22.21   +20 29 56.7         15DA225   G37  C~1zPy      
2015 03  23.14108  08 18 02.77   +20 29 48.8   22.7R 15DA225   695  C~1zPy      
2015 03  23.20667  08 18 02.61   +20 29 48.6         15DA225   695  C~1zPy      
2015 03  23.26825  08 18 02.45   +20 29 48.5         15DA225   695  C~1zPy      
2016 03  13.14698  08 24 46.99   +19 12 52.9   22.7R 15DA225   G37  C~1zPy      
2016 03  13.18670  08 24 46.85   +19 12 53.5         15DA225   G37  C~1zPy      
2017 12  20.47860  08 44 22.455  +16 19 35.16  23.4R 15DA225   G37  C~2Uy2      
2017 12  20.51822  08 44 22.281  +16 19 35.54        15DA225   G37  C~2Uy2      
2021 01  11.417360 09 01 04.400  +12 09 59.99  23.4G 15DA225   G37  C~4UG9      
2021 01  11.457960 09 01 04.166  +12 10 00.33        15DA225   G37  C~4UG9      
2021 01  11.498350 09 01 03.979  +12 10 00.82        15DA225   G37  C~4UG9      

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     0.04       0.00    -0.02
     2   0.0001      0.00     0.12       0.00    -0.06
     3   0.0003      0.00    -0.03       0.00    -0.28
     4   0.0711      0.00    -0.32       0.00     0.26
     5   0.0713      0.00    -0.44       0.00    -0.14
     6   0.0903      0.00     0.14       0.00     0.06
     7   0.0905      0.00     0.24       0.00     0.02
     8   0.0906      0.00     0.18       0.00     0.08
     9   1.0650      0.00     0.02       0.00    -0.12
    10   1.0651      0.00     0.05       0.00     0.37
    11   2.8373      0.00    -0.01       0.00    -0.21
    12   2.8374      0.00    -0.10       0.00    -0.01
    13   5.8980      0.00     0.08       0.00     0.00
    14   5.8981      0.00    -0.20       0.00    -0.04
    15   5.8983      0.00     0.19       0.00     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.

15DA225    quality flag:3

Type:       SCATNEAR  SCATNEAR  SCATNEAR

axisobj        73.650    73.649    73.650
ecceobj         0.514     0.514     0.514
incobj         27.612    27.612    27.612
qmin           33.684    33.590    33.778
qmax          115.443   115.545   116.289
amean          73.360    73.485    73.670
amin           72.156    72.158    72.338
amax           74.941    75.214    75.361
emean           0.522     0.521     0.523
emin            0.499     0.500     0.502
emax            0.541     0.541     0.543
imean          28.463    28.601    28.504
imin           27.574    27.540    27.715
imax           29.833    29.822    29.730
excite_mean     0.707     0.708     0.708
fracstop        1.000     1.000     1.000
cjmean          2.751     2.751     2.751

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       177.5     170.9     180.3
kozaiamp        180.0     180.0     180.0