BackForwardInstrument:  SOLSTICE 

Instrument details
Full name Solar/Stellar Irradiance Comparison Experiment
Purpose To compare the UV output of the sun with similar radiation produced by 30 stable, bright blue stars. The stars constitute the standards against which the solar irradiance is measured
Short description Three-channel grating spectrometer to measur solar and stellar irradiation (UV radiation in the ranges 119-190 nm (spectral resolution 0.1 nm), 170-320 nm (resoluion 0.25 nm), and 280-420 nm (resolution 0.35 nm).
Background New development
Scanning Technique Pointing Sun in daylight, one of the 30 calibrating stars during night
Resolution N/A
Coverage / Cycle N/A
Mass 36 kg Power 33 W Data Rate 740 bps


Providing Agency NASA
Instrument Maturity Flown on an R&D satellite
Utilization Period: 1991 to 2020
Last update: 2022-07-25
Detailed characteristics
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 future satellites

Instrument classification
  • Earth observation instrument
  • Passive optical radiometer or spectrometer
  • Solar irradiance monitor
WIGOS Subcomponents
  • Subcomponent 2
  • Solar magnetograph, solar EUV/X-ray imagery and EUV/X-ray irradiance, both on the Earth-Sun line and off the Earth-Sun line
  • Solar UV spectrometer [from L1, GEO, LEO]
Mission objectives
Primary mission objectives
  • Downward short-wave irradiance at TOA
Evaluation of Measurements

The following list indicates which measurements can typically be 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
Note: * Primary mission objective.
VariableRelevance for measuring this variableOperational limitationsExplanation
Downward short-wave irradiance at TOA*5 - marginalNo specific limitation.Spectral irradiance limited to UV and VIS