Orbit Fit and Astrometric record for 15GQ50

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: 15GQ50    
# Created Mon Dec 18 02:38:10 2017
# Orbit generated from Bernstein formalism
# Fitting   13 observations of   13
# Arc:   0.91y
# First observation: 2015/04/13
#  Last observation: 2016/03/09
Preliminary a, adot, b, bdot, g, gdot:
  -0.000036   0.014871   0.000000  -0.002992   0.018868   0.000000
# Chi-squared of fit:    23.30 DOF:   20 RMS:  0.24
# Min/Max residuals:    -0.53    0.50
# Exact a, adot, b, bdot, g, gdot:
  1.151281E-05  1.481346E-02 -3.097104E-06 -3.009449E-03  1.911791E-02  1.581231E-03
# Covariance matrix:
  2.9896E-13  1.0455E-12  9.8368E-15 -2.1728E-13  8.7047E-13  7.9866E-11
  1.0455E-12  4.4413E-11  3.1605E-13 -6.4095E-12  1.8885E-11  2.3730E-09
  9.8368E-15  3.1605E-13  1.6713E-13 -2.9201E-13  1.3936E-13  1.7387E-11
 -2.1728E-13 -6.4095E-12 -2.9201E-13  2.1405E-12 -2.8833E-12 -3.5429E-10
  8.7047E-13  1.8885E-11  1.3936E-13 -2.8833E-12  9.2339E-12  1.0656E-09
  7.9866E-11  2.3730E-09  1.7387E-11 -3.5429E-10  1.0656E-09  1.3112E-07
#      lat0       lon0       xBary       yBary       zBary        JD0
   -1.168581 -154.442714    0.048865   -0.020210   -0.998326  2457125.629458
# Heliocentric elements and errors
Epoch:              2457120.5000  =  2015/04/08
Mean Anomaly:          137.93687 +/-     5.886
Argument of Peri:       36.21664 +/-     5.717
Long of Asc Node:       19.86528 +/-     0.002
Inclination:            11.51642 +/-     0.004
Eccentricity:         0.17704199 +/-    0.0099
Semi-Major Axis:     46.63488374 +/-    0.1841
Time of Perihelion: 2412550.4987 +/-    1883.3
Perihelion:          38.37855117 +/-    0.4875
Aphelion:            54.89121630 +/-    0.5115
Period (y)              318.4744 +/-      1.89
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X          -48.10401259 +/-    0.0075
Ecliptic Y          -22.94818651 +/-    0.0036
Ecliptic Z           -1.06692641 +/-    0.0002
Ecliptic XDOT         0.00071570 +/-    0.0000
Ecliptic YDOT        -0.00201366 +/-    0.0000
Ecliptic ZDOT        -0.00043542 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   53.30810092 +/-    0.0069
Geocenter to KBO     52.30697834 +/-    0.0083
# Hcoef:  6.93

The following table shows the complete astrometric record for 15GQ50. 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 (15GQ50) followed by the observatory code and reference code for the source of the astrometry.

2015 04  13.12868  13 33 01.336  -10 58 09.26  24.0r 15GQ50    807  C~1x8u      
2015 04  13.21692  13 33 00.997  -10 58 07.35        15GQ50    807  C~1x8u      
2015 04  13.31061  13 33 00.648  -10 58 05.84        15GQ50    807  C~1x8u      
2015 04  18.11049  13 32 42.457  -10 56 29.61        15GQ50    304  C~1x8u      
2015 04  18.27813  13 32 41.795  -10 56 26.07  23.9r 15GQ50    304  C~1x8u      
2015 04  19.29706  13 32 37.943  -10 56 05.64        15GQ50    304  C~1x8u      
2015 05  22.09990  13 30 44.158  -10 45 49.88        15GQ50    304  C~1x8u      
2015 05  22.16487  13 30 43.960  -10 45 48.91        15GQ50    304  C~1x8u      
2015 05  23.08627  13 30 41.263  -10 45 33.93        15GQ50    304  C~1x8u      
2015 07  21.00164  13 29 30.491  -10 39 12.97        15GQ50    304  C~1x8u      
2015 07  21.06054  13 29 30.458  -10 39 13.22        15GQ50    304  C~1x8u      
2016 03  08.36395  13 38 00.121  -11 36 25.26        15GQ50    304  C~1x8u      
2016 03  09.36409  13 37 57.205  -11 36 11.30        15GQ50    304  C~1x8u      

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     0.15       0.00     0.13
  2   0.0002     -5.34     0.10      -0.05     0.27
  3   0.0005    -10.68     0.38      -0.52    -0.01
  4   0.0136   -295.21    -0.06      -8.91    -0.13
  5   0.0141   -305.58    -0.37      -9.18    -0.07
  6   0.0169   -365.85    -0.34     -10.92    -0.11
  7   0.1067  -2151.23     0.09     -52.48    -0.02
  8   0.1069  -2154.30     0.09     -52.65    -0.11
  9   0.1094  -2196.77    -0.01     -53.32     0.04
 10   0.2707  -3307.07     0.50     -82.68     0.20
 11   0.2709  -3307.43    -0.53     -83.09    -0.18
 12   0.9041   4929.99     0.35    -541.05    -0.08
 13   0.9069   4884.97    -0.35    -543.53     0.10

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.

15GQ50    quality flag:2

Type:       SCATEXTD  SCATNEAR  SCATEXTD

axisobj        46.233    46.915    45.867
ecceobj         0.184     0.215     0.168
incobj         11.585    11.581    11.589
qmin           37.298    36.216    37.738
qmax           56.120    58.759    54.900
amean          46.449    47.197    46.141
amin           46.032    46.738    45.748
amax           46.936    47.776    46.617
emean           0.180     0.214     0.165
emin            0.166     0.198     0.151
emax            0.196     0.232     0.179
imean          11.098    11.213    11.052
imin           10.510    10.445    10.491
imax           11.675    11.824    11.634
excite_mean     0.263     0.289     0.253
fracstop        1.000     1.000     1.000
cjmean          3.046     3.037     3.049

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     175.0     174.4
kozaiamp        180.0     179.9     180.0