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Updated Phase 3D Orbital Estimate -- for 24 hour launch delay

Below is the estimated State Vector and Keplerian Elements for 
the AMSAT Phase 3D spacecraft.  The vector data was computed from 
Arianespace orbital parameters at the time Phase 3D is scheduled 
to separate from the Ariane 5 upper stage.  The Keplerian Elements 
were computed, in turn, from the vector.  

Vector format = 10107
Satellite Name:         Phase 3D
Catalog Number:         93400            
Epoch MET:                  0.02983772000
                           0/00:42:57.979 MET
EFG E:                   4321.19714449000 km
    F:                   10857.0727900300 km
    G:                   -1323.5057345899 km
    Edot:                -3.1484853319000 km/s
    Fdot:                5.75560664520000 km/s
    Gdot:                -0.5488001613000 km/s
ndot/2 (drag):              0.00000000771 rev/day^2
nddt/6:                       0.00000E+00 rev/day^3
Bstar:                        1.25668E-05 1/Earth Radii
Elset #:                                1
Rev @ Epoch:                1.52588079822

Launch Window Opens:  2000-NOV-16 / 0107 UTC
Phase 3D separation:  Launch + 0042:57.979

The following Keplerian elements were computed from this vector and 
the scheduled date and time of the launch window opening.  Updated 
Keplerian elements will be computed from the vector, based on changes 
to the scheduled or actual launch time.

Phase 3D    
1 93400U            321.07636550  .00000001  00000-0  12567-4 0    14
2 93400   6.5034 247.6325 7357988 175.9296  13.3886  2.02435417    19

Satellite: Phase 3D    
Catalog number: 93400
Epoch time:        321.07636550
Element set:       1
Inclination:        6.5034 deg
RA of node:       247.6325 deg
Eccentricity:    0.7357988
Arg of perigee:   175.9296 deg
Mean anomaly:      13.3886 deg
Mean motion:    2.02435417 rev/day
Decay rate:    7.71000e-09 rev/day^2
Epoch rev:               1
Checksum:              276

Note that "93400" is a temporary Catalog Number.  A Permanent Catalog
Number and International Designator will be assigned when Phase 3D is
launched.  The satellite name will also be updated with the next 
sequential "OSCAR" designator.

These Keplerian elements represent a pre-launch estimate of Phase 3D's 
initial orbit.  The orbit will change significantly over the first year 
the spacecraft is on orbit.  Updates will be provided for significant 
orbital changes.

The Phase 3D launch team will be publishing a similar set of Keplerian
elements.  The data provided by the launch team will be "osculating"
parameters, compatible with AMSAT command station software. The 
osculating elements are the exact physical representation of the orbit
as opposed to the "mean" parameters provided in this bulletin.  I 
provide these mean elements as they are fully compatible with the NORAD
SGP4/SDP4 orbit propagation algorithms.  Tracking software that uses
the NORAD propagators should use the "mean" Keplerian elements provided
herein for the most accurate result.  Tracking software using non-NORAD
orbit propagation methods should use the "osculating" elements provided
by the Phase 3D launch team for the most accurate results.

Ken Ernandes, N2WWD

Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
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