WOptical spectrometer
WSpectrometer
WAlice (spacecraft instrument)
WBES III
WCary 14 Spectrophotometer
WCompact Reconnaissance Imaging Spectrometer for Mars
WComputed tomography imaging spectrometer
WDobson ozone spectrophotometer
WDU spectrophotometer
WFluorometer
WGamma-ray spectrometer
WGamma Ray Spectrometer (2001 Mars Odyssey)
WGamma-Ray Imaging Spectrometer
WGammasphere
WGlobal-scale Observations of the Limb and Disk
WGlueX
WImaging spectrometer
WK-band multi-object spectrograph
WMars Reconnaissance Orbiter
WMini-TES
WMulti-unit spectroscopic explorer
WNear Infrared Camera and Multi-Object Spectrometer
WNondispersive infrared sensor
WOrbiting Carbon Observatory 3
WOzone monitoring instrument
WPlanetary Fourier Spectrometer
WPrism spectrometer
WScanning Habitable Environments with Raman and Luminescence for Organics and Chemicals
WSCIAMACHY
WScintillation counter
WSpecial Sensor Ultraviolet Limb Imager
WSpectronic 20
WTotal Ozone Mapping Spectrometer
WTristimulus colorimeter
WTropospheric Emissions: Monitoring of Pollution