We describe the radiometric performance and ground calibration results of the Europa Clipper Ultraviolet Spectrograph (Europa-UVS). Europa-UVS is a modest power (~8 W) ultraviolet spectrograph that is the sixth in a series of Alice/UVS instruments built by SwRI. Europa-UVS covers a 55-206 nm bandpass with approximately 0.6 nm spectral resolution over a 7.5° field of view with better than 0.25° spatial resolution on-axis. Europa-UVS also features three different observing modes to allow higher-than-normal spatial resolution observing as well as solar occultations of Europa. Both the high spatial resolution and solar occultation observations have reduced sensitivity when compared with nominal observations. Europa-UVS meets all performance requirements with margin, and is the first planetary UV spectrograph to feature a microchannel plate detector with curved borosilicate microchannel plates (expected to be less sensitive to gamma rays than traditional plates). Europa-UVS, like its predecessor JUICE-UVS, incorporates both timetagged pixel list and histogram observing with programmable acquisitions to maximize science return while minimizing data storage and downlink. Europa-UVS will search near Europa for water vapor plumes, examine the composition and structure of Europa’s atmosphere and surface, and characterize Europa's aurora.
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