Editing Mars Observer (section)

==== Attitude control and propulsion ====
:The spacecraft was [[3-axis stabilized spacecraft|three-axis stabilized]] with four [[reaction wheel]]s and twenty-four [[reaction engine|thrusters]] with 1,346 kilograms of propellant. The propulsion system was a  high thrust, monomethyl hydrazine/nitrogen tetroxide bipropellant system for larger maneuvers and a lower thrust [[hydrazine]] [[monopropellant rocket|monopropellant]] system for minor orbital corrections during the mission. Of the bipropellant thrusters, four located on the aft, provide 490 [[Newton (unit)|newtons]] of thrust for course corrections, control of the spacecraft during the Mars orbital insertion maneuver and large orbit corrections during the mission; another four, located on along the sides of the spacecraft, provide 22&nbsp;newtons for controlling roll maneuvers. Of the hydrazine thrusters, eight provide 4.5&nbsp;newtons to control orbit trim maneuvers; another eight provide 0.9&nbsp;newtons for offsetting, or "desaturating", the reaction wheels. To determine the orientation of the spacecraft, a [[Astrionics#Earth Horizon Sensor|horizon sensor]], a 6-slit star scanner, and five [[Sun sensor]]s were included.{{r|MOSafetyReview|MOLaunchPressKit}}