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JPL On-Line Ephemerides                                                Horizons
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Target body    : Wild 2                           {source : JPL#34-DASTCOM3}
Observer site  : GEOCENTRIC (Earth-center) (399)  {source : DE-0406LE-0406}
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Execution date : Sun Feb 28 09:29:52 1999  (Pasadena time)
Requested by   : PORT_LOGIN
Target radii   : {Unavailable}     
Primary body   : Sun         
Start time     : A.D. 1999-Jan-01 00:00:00.0000 UT      
Stop  time     : A.D. 2007-Apr-01 00:00:00.0000 UT      
Step-size      : 1440 minutes
Apparent coords: AIRLESS  
RA format      : HMS
Time format    : CAL 
Elev. cutoff   : NO
Airmass cutoff : NO
Daylight cutoff: NO 
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Initial heliocentric osc. elements wrt ecliptic and mean equinox of J2000.0:
  EPOCH=  2450560.5 != 1997-Apr-22.0000000 (TDB)                               
    EC= .5402213259999999  QR= 1.582618049        TP= 2450575.1272467          
    OM= 136.1562151        W= 41.768217           IN= 3.2426039                
Comet physical & dynamic parameters:
    GM= n.a.               RAD= n.a.              A1= 1.333E-9                 
    A2= 1.44D-10           M1= 7.                 M2= 12.5                     
    k1= 15.                k2= 10.                PHCOF= n.a.                  
*****************************************************************************************************************************************************************************************************************************************************************************************
 Date__(UT)__HR:MN     R.A._(ICRF/J2000.0)_DEC R.A.__(a-apparent)__DEC dRA*cosD d(DEC)/dt  T-mag  N-mag Illu% Def_illu Ang-diam hEcl-Lon hEcl-Lat         r          rdot      delta       deldot   1-way_LT   VmagSn   VmagOb    S-E-O    S-O-E O-E-M/Illu% E-P-O PsAng PsAMV PlAng Cnst
*****************************************************************************************************************************************************************************************************************************************************************************************

Time

The TDB uniform time scale is used internally. Conversion between TDB and the selected non-uniform UT output scale has not been determined for UTC times after the next July or January 1st. The last known leap-second is used over any future interval.

Column Meaning

 

R.A._(ICRF/J2000.0)_DEC =

J2000.0 astrometric right ascension and declination of target. Corrected for light-time. Units: HMS (HH MM SS.ff) and DMS (DD MM SS.f)
 

R.A._(a-apparent)__DEC. =

Airless apparent right ascension and declination of target. Corrected for light-time, stellar aberration, precession, nutation and deflection of light due to the Sun & Earth. Units: HMS (HH MM SS.ff) and DMS (DD MM SS.f)
 

dRA*cosD d(DEC)/dt =

The rate of change of target RA and DEC. d(RA)/dt is multiplied by the cosine of the declination. Units: ARCSECONDS PER HOUR
 

T-mag N-mag =

Comet's approximate apparent visual total magnitude ("T-mag") and nuclear magnitude ("N-mag") by following definitions:
    T-mag = M1 + 5*log10(delta) + k1*log10(r)
    N-mag = M2 + 5*log10(delta) + k2*log10(r) + phcof*beta
Units: none
 

Illu% =

Fraction of target circular disk illuminated by Sun (phase), as seen by observer. Units: PERCENT
 

Def_illu =

Defect of illumination. Maximum angular width of target circular disk diameter not illuminated by the Sun. Units: ARCSECONDS
 

Ang-diam =

The equatorial angular width of the target body full disk, if it were fully visible to the observer. Units: ARCSECONDS
 

hEcl-Lon hEcl-Lat =

Geometric heliocentric J2000 ecliptic longitude and latitude of target at the instant light leaves it to be observed at print time (print time minus 1-way light-time). Units: DEGREES
 

r rdot =

Target apparent heliocentric range ("r") and range-rate ("rdot") as seen by observer. Units: AU and KM/S
 

delta deldot =

Target apparent range ("delta") and range-rate ("delta-dot") relative to observer. Units: AU and KM/S
 

1-way_LT =

Target 1-way light-time, as seen by observer. The elapsed time since light (observed at print-time) left or reflected off the target. Units: MINUTES
 

VmagSn VmagOb =

Magnitude of target velocity wrt Sun ("VmagSn") and the observer ("VmagOb") at time light left object to be observed (print time minus 1-way light-time). Units: KM/S
 

S-E-O (Theta) =

Sun-Earth-Object angle; target's apparent solar elongation seen by Earth observer at print-time. Units: DEGREES
 

S-O-E (Beta) =

Sun-Object-Earth angle; target's apparent phase angle at observation time on Earth. Units: DEGREES
 

O-E-M/Illu% (Moon/Illum) =

Obj-Earth-Moon/Illum%; apparent angle seen by Earth observer and the percent of the lunar disk illuminated by the Sun. Units: DEGREES and PERCENT
 

E-P-O =

Earth-Primary-Object angle; apparent angle between a target satellite, its primary's center and Earth-based observer at observation time. Units: DEGREES
 

PsAng PsAMV =

The position angles of the extended Sun->target radius vector ("PsAng") and the negative of the target's heliocentric velocity vector ("PsAMV"), as seen in the observer's plane-of-sky, measured CCW from reference frame North Celestial Pole. Small-bodies only. Units: DEGREES.
 

PlAng =

Angle between observer and target orbital plane, measured from center of target at the moment light seen at observation time leaves the target. Positive values indicate observer is above the object's orbital plane, in the direction of reference frame +z axis. Small-bodies only. Units: DEGREES.
 

Cnst =

Constellation ID; the 3-letter abbreviation for the constellation name of target's astrometric position, as defined by IAU (1930) boundary delineation. See documentation for list of abbreviations.