4.0 Mission Details
|T+45:00 min||LEO Delivery of Upper Stage|
|T+2:00:00 hr||Interplanetary Injection DV = 6.31 km/s|
|T+2.73 year||Powered Flyby (Semi-circularizing) Burn DV = 0.82 km/s|
|T+2.73 year||Heliocentric Z Component Addition Burn DV = 1.14 km/s|
With the help of the data from hohangle.f and position.f the following launch dates were chosen based primarily to provide significant displacements between each orbit. Also, the first two launches are temporally spread out to provide ample time for any redesign or upgrading in the final launches that may be found critical for the operation of P-STAR.
|Launch Date||Long. Asc. Node||1||2||3||4||5||6|
|02 - 06 - 2000||129º||-||-162º||-225º||103º||69º||32º|
|07 - 19 - 2005||291º||162º||-||-62º||229º||231º||194º|
|09 - 22 - 2007||353º||225º||62º||-||327º||293º||256º|
|10 - 26 - 2008||26º||-103º||-229º||-327º||-||-34º||-71º|
|11 - 30 - 2009||60º||-69º||-231º||-293º||34º||-||-37º|
|01 - 04 - 2011||97º||-32º||-194º||-256º||71º||37º||-|
Note that the table lists the differences in each transponder's longitude of ascending node. The closest two orbits are Transponders 1 and 6 with only a 32º separation in the X-Y plane, but they have an almost 60º (calculated from a 12.7 year period and 11 year period between delivery) difference in argument of perihelion, providing ample displacement.
This is not the best of situations for the comm design team to be in. At 5-6 AU (and farther considering the orbits are slightly eccentric) Solar power is not what it is in the Earth orbit environs. To make matters worse, there has been a worldwide outspoken resistance to Radio Thermal Generators (nuclear power supplies based upon a decaying isotopes thermal energy) not to mention full fledged fission reactors. It is not clear if a fission reactor could even be designed to fit within the mass constraints of the current P-STAR launch and delivery regime.
So one must assume rather large Solar arrays which will siphon vital mass from the actual comm and chronometer subsystems of each transponder, yet there may be a silver lining to this cloud of power limitations. It is conceivable that a large array could:
|Launch Mission A|
|Launch Mission B|
|Correct Trajectory A|
|Launch Mission C|
|Correct Trajectory B|
|Encounter with A|
|Correct Trajectory C|
|Correct Trajectory B|
|Encounter with C|
|Encounter with B|
Where mission A and C would be mid-length tracking missions and mission C would be a longer tracking mission. With standard team maintenance and automated tracking during cruise periods and focused attention where needed by the special operations team, a large number of missions could be tracked using two very skilled, very experienced, but small and utilitarian tracking groups.
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