Orbital GEOStar-3 Bus - Manual

Satellite Bus
• Increased power system capability to
provide 8 kW of payload power
• Structure accommodates up to 800 kg
payload mass and 4.8 kW payload
conducted thermal dissipation
• Compatibility with all commercially
available launch vehicles allowing
greater flexibility and lower launch cost
• Ability to dual manifest two spacecraft
as a tandem launch on select launch
vehicles
• Incorporation of flight-proven, low-risk
components
• Configure-to-order flexibility to
optimize customer value
FACTS AT A GLANCE
GEOStar
™
-3 Bus
A Fully Redundant Spacecraft Bus Designed for Geosynchronous Missions
GEO
Design
The GEOStar-3 satellite platform represents an evolutionary growth of Orbital's GEOStar-2 platform,
providing an incremental expansion of the flight-proven GEOStar-2 product line. EPS enhancements
include an increase in battery capacity and in solar array power, enabling GEOStar-3 to provide up
to 8,000 watts of power to the payload at end-of-life. The larger solar arrays and additional battery
capacity retain the 100 percent successful flight heritage 36 volt regulated power bus. The GEOStar-3
Bus structure’s mass carrying capability and propellant tank accommodation enable optimal use of
launch vehicle performance, and can include tandem launch missions that use heritage bi-propellant
apogee engines to ensure fast and reliable orbit raising. For heavier missions, a flight proven Electric
Propulsion system will replace the heritage ImpEHTs for stationkeeping operations.
Payload Accommodations
The GEOStar-3 Bus can accommodate payloads of up to 800 kilograms and 8,000 watts. As many as
72 radiatively cooled TWTAs, or a greater combination of radiatively and conductively cooled TWTAs can
easily be accommodated on the platform. The total payload conductive thermal dissipation is scalable up
to 4,800 watts. The platform can accommodate a broad range of depoyable reflectors and nadir antenna
configurations, enabling compelling payload solutions. The expanded payload envelope of GEOStar-3 also
allows customers to consider a larger universe of hosted payload opportunities.
Tandem Launch Configuration