Spacecraft:
The KOMPSAT-1 spacecraft is based on a TRW-developed standardized bus (of TOMS-EP heritage, including a MIL-STD-1555B communications bus) that can be easily modified to support a variety of mission requirements. A core (or equipment) module houses the housekeeping functions - power, telemetry and data handling, attitude control - needed on all space missions. A payload module hosts mission-unique equipment, KOMPSAT's imaging instruments and space physics experiments. A third module, housing a monopropellant hydrazine propulsion system, provides on-orbit thrust and station-keeping.
The spacecraft size of KOMPSAT-1 is 1.33 m in diameter and 2.33 m in length. The platform uses a three-axis stabilized bus with a reaction control subsystem module, providing a 2-sigma pointing accuracy of 0.01º (roll), 0.18º (pitch) and 0.50º (yaw), and a pointing knowledge of 0.08º (roll and pitch) and 0.10º (yaw). The S/C mass is 510 kg (including 73 kg hydrazine), power = 630 W (500 W EOL), the S/C design life is three years.