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Sun pointing spacecraft, spin stabilized at 15 RPM


-Autonomous sun acquisition and spin-up from any orientation  

-On-orbit inertia adjustment aligns imager with spin axis  

-On-orbit mass properties adjustment direct sun pointing error measurement to ~0.05 degrees 

-Magnetic torqrods used for all control 

-Sun pointing (precession) control to <0.2 degrees 

-Spin rate stability to <4.5 arcseconds per second 

link to On-Orbit Configuration 
link to Mode Definitions and Transitions