Orbit Fit and Astrometric record for 98WV31

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: 98WV31    
# Created Sun Nov 22 02:37:10 2009
# Orbit generated from Bernstein formalism
# Fitting   17 observations of   20
# Arc:   9.95y
# First observation: 1998/11/19
#  Last observation: 2008/11/01
Preliminary a, adot, b, bdot, g, gdot:
   0.000553   0.034426   0.000020   0.003261   0.031701   0.000000
# Chi-squared of fit:    12.29 DOF:   28 RMS:  0.15
# Min/Max residuals:    -0.38    0.31
# Exact a, adot, b, bdot, g, gdot:
  1.847414E-05  3.593409E-02  6.202542E-07  3.397459E-03  3.127094E-02  7.828623E-03
# Covariance matrix:
  4.2654E-13 -5.9423E-13  7.1105E-15 -4.9219E-14  6.8660E-13 -1.5034E-12
 -5.9423E-13  1.4572E-12 -2.4487E-14  1.2773E-13 -9.4831E-13  3.8823E-12
  7.1105E-15 -2.4487E-14  1.2249E-13 -1.5542E-14  4.5527E-15 -6.7337E-14
 -4.9219E-14  1.2773E-13 -1.5542E-14  1.6590E-14 -7.5398E-14  3.4284E-13
  6.8660E-13 -9.4831E-13  4.5527E-15 -7.5398E-14  1.9274E-12 -2.3233E-12
 -1.5034E-12  3.8823E-12 -6.7337E-14  3.4284E-13 -2.3233E-12  1.0416E-11
#      lat0       lon0       xBary       yBary       zBary        JD0
   -1.905242   39.209747   -0.300509   -0.031411   -0.936876  2451136.590871
# Heliocentric elements and errors
Epoch:              2451130.5000  =  1998/11/13
Mean Anomaly:           39.68182 +/-     0.025
Argument of Peri:      274.92416 +/-     0.028
Long of Asc Node:       58.56319 +/-     0.000
Inclination:             5.71358 +/-     0.000
Eccentricity:         0.27658645 +/-    0.0002
Semi-Major Axis:     39.63718918 +/-    0.0130
Time of Perihelion: 2441083.3746 +/-       4.1
Perihelion:          28.67407956 +/-    0.0121
Aphelion:            50.60029881 +/-    0.0183
Period (y)              249.5528 +/-      0.12
# Ecliptic coordinates at JD0 (AU and AU/d)
Ecliptic X           25.30886045 +/-    0.0011
Ecliptic Y           21.02964203 +/-    0.0009
Ecliptic Z           -1.06313445 +/-    0.0000
Ecliptic XDOT        -0.00145101 +/-    0.0000
Ecliptic YDOT         0.00288614 +/-    0.0000
Ecliptic ZDOT         0.00027448 +/-    0.0000
# Distances at JD0 (AU)
Heliocenter to KBO   32.92285705 +/-    0.0010
Geocenter to KBO     31.97857630 +/-    0.0014
# Hcoef:  8.09

The following table shows the complete astrometric record for 98WV31. 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 (98WV31) followed by the observatory code and reference code for the source of the astrometry.

1998 11  19.09014  02 29 45.19   +12 45 25.3   22.3R 98WV31    695   a3608      
1998 11  19.17149  02 29 44.73   +12 45 23.3         98WV31    695   a3608      
1998 11  19.24648  02 29 44.29   +12 45 21.6         98WV31    695   a3608      
1998 12  17.85605  02 27 26.66   +12 36 04.9   22.6R 98WV31    950   a3608      
1998 12  17.88994  02 27 26.54   +12 36 04.3         98WV31    950   a3608      
1998 12  17.92538  02 27 26.40   +12 36 03.8         98WV31    950   a3608      
1998 12  18.83184  02 27 23.12   +12 35 52.0   22.6R 98WV31    950   a3608      
1998 12  18.88479  02 27 22.93   +12 35 51.0         98WV31    950   a3608      
1999 01  22.22925  02 26 24.01   +12 34 05.2   22.4R 98WV31    568  Ca5545      
1999 01  23.24738  02 26 24.36   +12 34 12.8         98WV31    568  Ca5545      
1999 11  10.27125  02 38 23.06   +13 38 34.6   22.4R 98WV31    695  Ca7322      
1999 11  10.36797  02 38 22.46   +13 38 32.3         98WV31    695  Ca7322      
1999 11  11.26736  02 38 17.12   +13 38 09.7   23.2R 98WV31    695  Ca7322      
1999 11  11.36240  02 38 16.59   +13 38 07.4         98WV31    695  Ca7322      
2002 11  05.41694  03 01 39.44   +15 58 11.2   22.5R 98WV31    568  Cl8244      
2002 11  05.47431  03 01 39.09   +15 58 10.0         98WV31    568  Cl8244      
2008 11  01.60652  03 45 33.37   +19 48 23.1   26.0R 98WV31    250  S~06AK      
2008 11  01.61346  03 45 33.32   +19 48 23.0         98WV31    250  S~06AK      
2008 11  01.61971  03 45 33.29   +19 48 23.1         98WV31    250  S~06AK      
2008 11  01.62666  03 45 33.25   +19 48 22.9         98WV31    250  S~06AK      

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    -0.06       0.00     0.23
  2   0.0002     -7.02     0.03       0.23     0.16
  3   0.0004    -13.66    -0.04       0.65     0.31
  4   0.0788  -2100.43    -0.06     111.30     0.15
  5   0.0788  -2102.29     0.01     111.28    -0.03
  6   0.0789  -2104.39    -0.07     111.46    -0.03
  7   0.0814  -2153.67     0.13     115.55    -0.05
  8   0.0816  -2156.63     0.11     115.49    -0.38
  9   0.1756  -3008.09     0.20     290.05    -0.10
 10   0.1784  -3000.81    -0.27     295.62     0.04
 11   0.9752   8184.55     0.06     671.07    -0.38
 12   0.9754   8175.51    -0.08     671.58    -0.14
 13   0.9779   8094.36     0.06     674.04     0.16
 14   0.9782   8086.29 (   0.71)    674.23 (   0.08)
 15   3.9626  30214.93 (  -0.84)   2702.53 (   0.42)
 16   3.9627  30209.63 (  -0.82)   2702.81 (   0.56)
 17   9.9535  72691.73     0.07    6687.36    -0.10
 18   9.9535  72690.93    -0.10    6687.42    -0.05
 19   9.9535  72690.49     0.03    6687.62     0.14
 20   9.9536  72689.82    -0.01    6687.54     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.

98WV31    quality flag:3

Type:           3:2E      3:2E      3:2E

axisobj        39.661    39.700    39.623
ecceobj         0.276     0.276     0.275
incobj          5.710     5.710     5.710
qmin           28.401    28.408    28.398
qmax           50.857    50.813    50.897
amean          39.454    39.454    39.454
amin           39.277    39.311    39.238
amax           39.663    39.621    39.712
emean           0.269     0.265     0.271
emin            0.258     0.250     0.262
emax            0.282     0.283     0.282
imean           5.319     6.058     4.957
imin            4.728     4.701     4.383
imax            5.686     7.198     5.599
excite_mean     0.285     0.285     0.284
fracstop        1.000     1.000     1.000
cjmean          2.958     2.958     2.958

libcent 0       179.8     179.8     180.5
libamp  0        80.3      61.7      97.1
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       171.2     164.9     180.7
kozaiamp        180.0     180.0     180.0