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We analyze EUV spectra of the full solar disk from the Cosmic HotInterstellar Plasma Spectrometer (CHIPS) spanning a period of two years. Theobservations were obtained via a fortuitous off-axis light path in the 140 --270 Angstrom passband. The general appearance of the spectra remainedrelatively stable over the two-year time period, but did show significantvariations of up to 25% between two sets of Fe lines that show peak emission at1 MK and 2 MK. The variations occur at a measured period of 27.2 days and arecaused by regions of hotter and cooler plasma rotating into, and out of, thefield of view. The CHIANTI spectral code is employed to determine plasmatemperatures, densities, and emission measures. A set of five isothermalplasmas fit the full disk spectra well. A 1 -- 2 MK plasma of Fe contributes85% of the total emission in the CHIPS passband. The standard DifferentialEmission Measures (DEMs) supplied with the CHIANTI package do not fit the CHIPSspectra well as they over-predict emission at temperatures below log(T) = 6.0and above log(T) = 6.3. The results are important for cross-calibrating TIMED,SORCE, SOHO/EIT, and CDS/GIS, as well as the recently launched Solar DynamicsObservatory.

EUV Spectra of the Full Solar Disk: Analysis and Results of the Cosmic Hot Interstellar Plasma Spectrometer (CHIPS)