SESS / Special Sensor Ultraviolet Spectrographic Imager
To measure UV radiation from the Earth's atmosphere and ionosphere, also measuring visible radiation (airglow and terrestrial albedo).
Assemblage of a scanning Imaging spectrometer and a nadir-looking photometer system. The spectrometer has 160 spectral channels in 5 selectable sub-ranges of the Far UV interval from 115 to 180 nm, inclusive of the H Lyman-alpha line at 121.6 nm. The photometer monitors airglow at 427.8 and 630 nm and the terrestrial albedo near 630 nm
Part of the SESS (Space Environment Sensor Suite) package
Scanning spectrometer: cross-track scan up to beyond the horizon opposite to sun, till tangent altitude of 520 km; fast scanning along-track of 16 IFOVs. Swath: 3000 km. Photometer: nadir only
UV: 10 km at s.s.p., 300 km for limb viewing; VIS: 25 km at s.s.p.
Coverage / Cycle
Global, daily. UV sampled at 22 s intervals, VIS at 180 s intervals
Flown on operational programme
2003-11-20 to 2016-02-11
Satellites this instrument is flying on
Note: a red tag indicates satellites no longer operational, a
green tag indicates operational satellites, a blue tag indicates
Solar and space environment monitors Space radiometer or spectrometer
No WIGOS subcomponents have been defined.
Primary mission objectives
Secondary mission objectives
UV flux spectrum UV sky image Opportunity objectives Electron Density Ionospheric plasma density Show all Show fewer
Tentative Evaluation of Measurements
The following list indicates which measurements can
retrieved from this category of instrument. To see a full Gap Analysis by Variable,
click on the respective variable.
Note: table can be sorted by clicking on the column headers
Variable Relevance for measuring this variable Operational limitations Explanation
UV flux spectrum 1 - primary No specific limitation. Earth's limb observed, high spectral resolution
UV sky image 1 - primary No specific limitation. Earth's limb observed, spectrometry with high spatial resolution
Aurora 1 - primary No specific limitation. Observed down to Earth's surface in UV and VIS
Ionospheric plasma density 5 - marginal No specific limitation. UV imaging spectrometer measuring ionospheric plasma density in the Earth's limb
Electron Density 5 - marginal No specific limitation. UV spectrometry of the Earth's limb