BackForwardInstrument:  HiRI 

Instrument details
Acronym HiRI
Full name High-Resolution Imager
Purpose Very-high-resolution land and vegetation observation.  Digital Elevation Model (DEM)
Short description Two parallel radiometers, 5 VNIR channels, 4 multi-spectral (MS), one panchromatic (PAN) [see detailed characteristics below]
Background Consolidated technology
Scanning Technique Pushbroom, 7500 pixel/line (MS), 30000 pixel/line (PAN), swath 20 km s.s.p.; cross-track and along-track pointing capability by up to ± 30° off-nadir.  By combining cross- and along- track capabilities, composite images of 120 km x 120 km may be built.  Stereoscopic capability in-orbit and between successive orbits
Resolution 2.8 m (MS), 0.7 m (PAN)
Coverage / Cycle Global coverage in 26 days, in daylight.  With strategic pointing, one place can be observed every 2 days.
Mass 200 kg Power 400 W Data Rate 465 Mbps

 

Providing Agency CNES
Instrument Maturity Flown on operational programme
Utilization Period: 2012 to 2025
Last update: 2023-11-27
Detailed characteristics
Central wavelength Spectral interval SNR @ specified albedo
0.49 µm 0.45 - 0.53 µm 141 @ 50 % albedo, SZA 60°
0.55 µm 0.52 - 0.58 µm 139 @ 50 % albedo, SZA 60°
0.66 µm 0.62 - 0.70 µm 145 @ 50 % albedo, SZA 60°
0.83 µm 0.78 - 0.89 µm 184 @ 70 % albedo, SZA 60°
N/A (PAN) 0.48 - 0.90 µm 145 @ 50 % albedo, SZA 60°
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
  • High resolution optical imager
WIGOS Subcomponents
  • Subcomponent 4
  • High-resolution optical observation constellation (commercial)
  • High-resolution optical observation constellation (commercial)
Mission objectives
Primary mission objectives
  • Biomass
  • Fraction of Absorbed PAR (FAPAR)
  • Fraction of vegetated land
  • Land cover
  • Leaf Area Index (LAI)
  • Normalised Difference Vegetation Index (NDVI)
  • Vegetation type
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
Biomass*5 - marginalCloud sensitive.. Index only.. Infrequent coverage.. Daylight only.VIS and NIR channels. Biomass inferred from NDVI
Cloud cover5 - marginalInfrequent coverage.. Daylight only.VIS and NIR channels
Cloud optical depth4 - fairLow-density cloud only.. Infrequent coverage.. Daylight only.VIS and NIR channels
Earth surface albedo5 - marginalCloud sensitive.. Infrequent coverage.VIS channels
Fire fractional cover2 - very highCloud sensitive.. Daylight only.VIS channels with high resolution for boundary detection
Fraction of Absorbed PAR (FAPAR)*4 - fairCloud sensitive.. Infrequent coverage.VIS channels including Red at 700 nm
Fraction of vegetated land*2 - very highCloud sensitive.. Daylight only.VIS and NIR channels
Glacier cover4 - fairCloud sensitive.. Long time for mapping.. Daylight only.VIS and NIR channels; and panchromatic channel with high resolution, for glacier boundary detection
Glacier topography5 - marginalCloud sensitive.. Long time for mapping.. Daylight only.VIS and panchromatic channels with cross-track steering capability for stereoscopy between images from neighbour orbits
Ice sheet topography5 - marginalCloud sensitive.. Long time for mapping.. Daylight only.VIS and panchromatic channels with cross-track steering capability for stereoscopy between images from neighbouring orbits
Land cover*2 - very highCloud sensitive.. Daylight only.VIS and NIR channels
Land surface topography5 - marginalCloud sensitive.. Long time for mapping.. Daylight only.VIS and panchromatic channels with cross-track steering capability for stereoscopy between images from neighbour orbits
Leaf Area Index (LAI)*4 - fairCloud sensitive.. Daylight only.. Infrequent coverage.VIS and NIR channels. LAI inferred from NDVI
Normalised Difference Vegetation Index (NDVI)*2 - very highCloud sensitive.. Infrequent coverage.VIS and NIR channels
Photosynthetically Active Radiation (PAR)4 - fairCloud sensitive.. Infrequent coverage.VIS channels, range undersampled
Sea-ice cover5 - marginalCloud sensitive.. Daylight only.VIS and NIR (for contour enhancement) channels
Short-wave cloud reflectance5 - marginalInfrequent coverage.VIS and NIR channels. Unsuitable dynamic range (saturation)
Snow cover4 - fairCloud sensitive.. Infrequent coverage.. Daylight only.VIS, NIR and panchromatic (higher resolution) channels
Soil moisture at surface5 - marginalCloud sensitive.. Index only.. Infrequent coverage.. Daylight only.VIS and NIR channels. Soil moisture inferred from differential brightness
Soil type2 - very highCloud sensitive.. Daylight only.VIS and NIR channels
Upward short-wave irradiance at TOA5 - marginalSpectral interpolation needed.. Information on BRDF needed.. Infrequent coverage.VIS and NIR channels
Vegetation type*3 - highCloud sensitive.. Daylight only.VIS and NIR channels
Aerosol volcanic ash5 - marginalCloud sensitive.. Infrequent coverage.. Daylight only.VIS and NIR channels
Aerosol volcanic ash Total Column5 - marginalCloud sensitive.. Infrequent coverage.. Daylight only.VIS and NIR channels