Abstract: InordertoobtainhigherresolutionimagesofthewholelunarsurfaceandtakehighresolutionphotosofHong-Wanarea,whichisoneofthepreselectedlandingsiteofChang′E-3  (CE-3)    mission,theresolutionoftheCCDcameraofChang′E-2 (CE-2) satellitewasimproved.AndanimpulsewastakentomaneuverCE2fromtheheightof100 kmlunarcircularorbittoa100 km/15 kmellipticalorbit，whose perilune height was 15km and apolune height was 100 km tofurtherreducetheorbitalaltitudetotakephotosofHong-Wanareaneartheperilune.However,thesatellitecouldnotstayintheorbitforalongtimebecauseoftheenergylimitation.Thesunelevationoftheorbitwasalsorequiredtobehigherthan 15°forthesakeofhighqualityofimaging.Moreover,theprecisionrequirementsoforbitmeasurementanddeterminationdemandedenoughtrackingarcs.  Alltheserestrictionsbroughtforwardhighrequirementsforthedesign and control of the experiment orbit.Based on the engineering experience of Chang′E-1 mission,the characteristics of 100 km/15 km orbit with only academic stations considered to measure and control the satellite,andtwomethodswerepresentedtocalculatecontrolstrategiesoftheexperimentorbitincludingtimefixedignitionandfueloptimalmaneuveraccordingtotherequirementsoftheimagingconstraintsandorbitdetermination.Theresultsandtheerroranalysesshowthatthedesignmeetstheimagingrequirementsoftheexperimentorbit,anditisfeasiblewiththesafetyassuranceofthesatellite.

Key words: Deepspaceexploration, Orbitcontrol, Landingsite, Highresolutionimaging, Chang′E-2satellite