Rum, GiovanniGiovanniRumPortelli, ClaudioClaudioPortelliBussolino, LuigiLuigiBussolinoVaresio, FrancoFrancoVaresio2020-09-172020-09-171989-01-01https://hdl.handle.net/20.500.13025/11The Italian Research Interim Stage (IRIS) is described. It consists of a Shuttle upper stage system designed to inject light payloads up to 900 kg mass from the Shuttle circular parking orbit into a geostationary transfer orbit. A summary of the information included in the IRIS users manual provides users with the necessary performance data, environment and interfaces for their payloads. A review of the status of the project is presented. The first flight unit will be launched in Aug. 1991.EXPENDABLE STAGES (SPACECRAFT)GEOSYNCHRONOUS ORBITSIRIS SATELLITESITALIAN SPACE PROGRAMLAUNCH VEHICLESMISSION PLANNINGPARKING ORBITSPAYLOAD CONTROLSPACE SHUTTLE PAYLOADSSPACE TRANSPORTATION SYSTEMTRANSFER ORBITSconference paperhttp://adsabs.harvard.edu/abs/1989STIN...9026035B54dcce078580fe1368eeadf0