SPS Feasability Study SD76SA0239-2

ABBREVIATIONS ACS attitude control system Ag silver Al aluminum AMO air mass zero: No atmospheric filtering is solar cell performance measurements APS auxiliary propulsion system Au astrononical unit: Mean distance from earth to sun ( 92,900,000 miles) BOL beginning of life CER cost estimating relationship CRM crew and resupply module Cu copper CW continuous wave DBM decibels referenced to 1 milliwatt DPL diplexer ELV earth launch vehicle EM electromagnet: A type of Klystron EOL end of life EROI earth return orbit insertion EVA extra - vehicular activity FEP fluorinated ethylene propalene (teflon) FSTSAS Future Space Transportation Systems Analysis Study (Boeing) Ga gallium GaAs gallium arsenide GaAlAs gallium aluminum arsenide GEO geosynchronous equatorial orbit GFY government fiscal year GHz gigahertz GLOW gross lift off weight GSE ground support equipment GSTOI geosynchronous transfer orbit Insertion GW gigawatt HLLV heavy lift launch vehicle HTO-SSTO horizontal take off - single stage of orbit IOC initial operational capability I specific impulse (thrust/propellant weight flowrate) sp