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 Fri Dec 15 02:38:07 2017
# Orbit generated from Bernstein formalism
# Fitting   10 observations of   10
# Arc:   1.07y
# First observation: 2015/02/18
#  Last observation: 2016/03/13
Preliminary a, adot, b, bdot, g, gdot:
  -0.000002   0.030214   0.000007  -0.015865   0.027353   0.000000
# Chi-squared of fit:    10.30 DOF:   14 RMS:  0.18
# Min/Max residuals:    -0.36    0.25
# Exact a, adot, b, bdot, g, gdot:
  1.731826E-05  3.027510E-02 -9.420067E-06 -1.585370E-02  2.755879E-02 -6.375975E-03
# Covariance matrix:
  4.8566E-13  1.5623E-13  1.1234E-14 -1.6449E-13  1.2927E-12  9.1171E-12
  1.5623E-13  2.5828E-10  8.2406E-12 -1.7789E-10  7.3424E-11  1.0069E-08
  1.1234E-14  8.2406E-12  4.6995E-13 -5.9223E-12  2.3463E-12  3.2237E-10
 -1.6449E-13 -1.7789E-10 -5.9223E-12  1.2386E-10 -5.0318E-11 -6.9606E-09
  1.2927E-12  7.3424E-11  2.3463E-12 -5.0318E-11  2.5965E-11  2.8473E-09
  9.1171E-12  1.0069E-08  3.2237E-10 -6.9606E-09  2.8473E-09  3.9399E-07
#      lat0       lon0       xBary       yBary       zBary        JD0
    0.906560  122.555684   -0.437113    0.014125   -0.883029  2457071.660548
# Heliocentric elements and errors
Epoch:              2457070.5000  =  2015/02/17
Mean Anomaly:          352.01005 +/-     0.651
Argument of Peri:      207.34845 +/-     2.562
Long of Asc Node:      304.92882 +/-     0.001
Inclination:            27.55979 +/-     0.010
Eccentricity:         0.52526243 +/-    0.0128
Semi-Major Axis:     74.86336527 +/-    1.3793
Time of Perihelion: 2462321.5264 +/-     402.2
Perihelion:          35.54045240 +/-    1.1577
Aphelion:           114.18627814 +/-    2.3103
Period (y)              647.7572 +/-     17.90
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -20.37100095 +/-    0.0036
Ecliptic Y           31.08998422 +/-    0.0057
Ecliptic Z            0.57375898 +/-    0.0001
Ecliptic XDOT        -0.00221134 +/-    0.0000
Ecliptic YDOT        -0.00213690 +/-    0.0001
Ecliptic ZDOT        -0.00158473 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   37.17383486 +/-    0.0051
Geocenter to KBO     36.28606809 +/-    0.0067
# Hcoef:  7.18

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      

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     0.01       0.00     0.07
  2   0.0001     -3.35     0.09      -0.48     0.05
  3   0.0003     -6.80     0.01      -1.18    -0.21
  4   0.0711  -1529.10    -0.34    -255.77     0.17
  5   0.0713  -1532.16    -0.36    -256.89    -0.24
  6   0.0903  -1796.50     0.15    -326.18     0.06
  7   0.0905  -1798.64     0.25    -326.88     0.04
  8   0.0906  -1800.81     0.18    -327.49     0.08
  9   1.0650   4817.13     0.04   -3506.07    -0.25
 10   1.0651   4815.06    -0.05   -3505.95     0.24

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        74.259    77.574    72.212
ecceobj         0.520     0.551     0.498
incobj         27.606    27.576    27.636
qmin           33.624    32.968    33.972
qmax          116.301   125.055   111.618
amean          73.618    77.283    71.816
amin           72.228    75.823    70.851
amax           75.319    79.344    73.210
emean           0.525     0.554     0.506
emin            0.501     0.533     0.484
emax            0.545     0.576     0.527
imean          28.526    28.773    28.450
imin           27.709    27.669    27.404
imax           29.803    29.942    29.702
excite_mean     0.710     0.734     0.695
fracstop        1.000     1.000     1.000
cjmean          2.747     2.727     2.761

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       180.7     193.0     177.4
kozaiamp        180.0     180.0     180.0