Updated ISS info from MCC

From: Thomas Fly (thomasfly@j2ee-consultants.com)
Date: Thu Aug 19 2004 - 11:57:52 EDT

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    I'm now getting some info "straight from the horse's mouth."  I'm not yet sure how this information will impact the ISS
    TLEs posted on the SVPOST.html page (which I use to generate ISS transit goodies), but it does indicate the current
    orientation of the ISS, which can be fed into Mike Tyrrell and Phil Masding's ISS VRML simulator, to help with the
    interpretation of any video you may capture.
    
    This information "should not be used for precise applications or analysis" ... whatever that means ;-)
    
    Oddly enough, I also recently received information from the MCC that the MCC TLEs are based upon a True Equator / Mean
    Equinox (TEME) reference frame, while analysis of the simultaneous ISS / Venus transit suggested that they are
    referenced to MEME, while OIG TLEs are referenced to TETE:
    http://www.satobs.org/seesat/Aug-2004/0111.html
    
    However below, associated with what I assume is the raw data for the orbit determination vectors, it states:
         X axis = mean vernal equinox of epoch
         Z axis = earth mean rotation axis of epoch
    
    
    * Daily solar flux is predicted to be around 113 over the next 3 days.
    
    * Daily earth geomagnetic activity is predicted to be predominantly at quiet to unsettled levels over the next 3 days.
    There is the possibility for isolated active periods on prediction days 2 and 3.
    
    * ISS is scheduled to perform a orbit adjust-phasing maneuver early tomorrow UTC time. The current burn time is
    233:01:24:30 UTC and the maneuver delta-v is 1.3 meters/second. An updated orbital elements file will be sent out when a
    post-track vector becomes available.
    
    * ISS maneuvered to LVLH attitude mode at approximabely 232:01:14:00 UTC.
    
    
         The following on-orbit vector is provided by NASA
         Johnson Space Center Flight Design and Dynamics
         Division for use in ground track plotting programs.
         It should not be used for precise applications
         or analysis!
    
         Data were generated using application SPCM V4.0 DLL
    
    
         Vehicle = Current ISS
    
         Lift off time (UTC) : 2004/232:11:17:52.0000
    
         Vector time (UTC) :   2004/232:11:17:52.0000
         Vector time (MET) :      +   0: 0: 0: 0.0000
         Orbit :   825
         Weight (lbs) :      404131.10
         Area (sq ft) :        5000.00
         Drag Coefficient (Cd) :  2.00
         90 day mean solar flux (jansky) : 108.00
         12 month mean earth geomagnetic index :  2.79
    
         This vector is valid for prediction purposes until 234: 0: 0:  .0 UTC
    
    
                 M50 Cartesian                            M50 Keplerian
         ------------------------------           ------------------------------
         X    =    6723456.17                     A    =    6740465.06 meter
         Y    =     -80690.92 meter               E    =      .0012810
         Z    =    -429248.36                     I    =      51.66368
         XDOT =    432.022909                     Wp   =      66.22722
         YDOT =   4776.778056 meter/sec           RA   =       2.20607 deg
         ZDOT =   6015.067180                     TA   =     289.11397
                                                  MA   =     289.25263
                                                  Ha   =       200.294 n.mi
                                                  Hp   =       190.969
    
    
                 M50 Cartesian                            J2K Cartesian
         ------------------------------           ------------------------------
         X    =    22058583.23                    X    =    6725944.44
         Y    =     -264733.99 feet               Y    =      -5496.00 meter
         Z    =    -1408295.14                    Z    =    -396571.80
         XDOT =    1417.397995                    XDOT =    349.352103
         YDOT =   15671.844016 feet/sec           YDOT =   4781.146707 meter/sec
         ZDOT =   19734.472375                    ZDOT =   6016.965584
    
    
         M5O    = Inertial mean of year 1950 frame of reference
         Epoch  = beginning of Besselian year 1950
         X axis = mean vernal equinox of epoch
         Z axis = earth mean rotation axis of epoch
         Y axis = completes right handed cartesian earth centered system
    
         J2K    = Inertial mean of year 2000 frame of reference
         Epoch  = Julian date 2451545.0 TDT
         X axis = mean vernal equinox of epoch
         Z axis = earth mean rotation axis of epoch
         Y axis = completes right handed cartesian earth centered system
    
    
         The mean element set is posted at a UTC for which position is
         just north of the next ascending node relative to the above
         vector time
    
    
                     USSPACECOM TWO LINE MEAN ELEMENT SET
    
    ISS
    1 25544U 98067A   04232.47149943  .00017467  00000-0  13994-3 0  9547
    2 25544  51.6329   2.6661 0005330 129.3272 230.8362 15.71066323  8260
    
    Satellite: ISS
    Catalog number: 25544
    Epoch time:      04232.47149943   =     yrday.fracday
    Element set:     954
    Inclination:       51.6329 deg
    RA of node:         2.6661 deg
    Eccentricity:     .0005330
    Arg of perigee:   129.3272 deg
    Mean anomaly:     230.8362 deg
    Mean motion:   15.71066323 rev/day
    Decay rate:    1.74670E-04 rev/day^2
    Epoch rev:             826
    Checksum:              280
    
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