BackForwardInstrument:  ASTER 

Instrument details
Acronym ASTER
Full name Advanced Spaceborne Thermal Emission and Reflection radiometer
Purpose High-resolution land and vegetation observation
Short description 14-channel radiometer in three sub-systems, VIS/NIR (3 channels),  SWIR (6 channels), TIR (5 channels) [see detailed characteristics below]
Background New development
Scanning Technique VNIR and SWIR pushbroom; 4000 pixel/line (VNIR), 2000 pixel/line (SWIR); TIR whiskbroom  (670 pixel/line;  swath 60 km s.s.p.; cross-track pointing capability within a range of  ± 318 km (VNIR) or ± 116 km (SWIR and TIR); along-track stereoscopic viewing in one NIR channel (0.81 µm)
Resolution Changing with channels group (see table)
Coverage / Cycle By exploiting strategic pointing, any place within 16 days, or within 5 days limited to VNIR in daylight
Mass 421 kg Power 463 W Data Rate 89.2 Mbps

 

Providing Agency METI
Instrument Maturity Flown on an R&D satellite
Utilization Period: 2000 to 2022
Last update: 2021-06-16
Detailed characteristics

Central wavelength

Spectral interval

SNR or NEΔT @ specified input

Resolution s.s.p.

0.56 µm

0.52-0.60 µm

140 @ 70% albedo

15 m

0.66 µm

0.63-0.69 µm

140 @ 70% albedo

15 m

0.81 µm

0.76-0.86 µm

140 @ 70% albedo

15 m

1.65 µm

1.60-1.70 µm

140 @ 70% albedo

30 m

2.165 µm

2.145-2.185 µm

54 @ 70% albedo

30 m

2.205 µm

2.185-2.225 µm

54 @ 70% albedo

30 m

2.260 µm

2.235-2.285 µm

54 @ 70% albedo

30 m

2.330 µm

2.295-2.365 µm

70 @ 70% albedo

30 m

2.395 µm

2.360-2.430 µm

54 @ 70% albedo

30 m

8.30 µm

8.125-8.475 µm

0.3 K @ 300 K

90 m

8.65 µm

8.475-8.825 µm

0.3 K @ 300 K

90 m

9.10 µm

8.925-9.275 µm

0.3 K @ 300 K

90 m

10.60 µm

10.25-10.95 µm

0.3 K @ 300 K

90 m

11.30 µm

10.95-11.65 µm

0.3 K @ 300 K

90 m
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 1
  • High-resolution multi-spectral VIS/IR imagers
  • High-resolution multi-spectral VIS/IR imager
Mission objectives
Primary mission objectives
  • Biomass
  • Leaf Area Index (LAI)
  • Normalised Difference Vegetation Index (NDVI)
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*4 - fairCloud sensitive.. Index only.. Infrequent coverage.. Daylight only.VIS, NIR and SWIR channels. Biomass inferred from NDVI and LAI
Cloud cover2 - very highInfrequent coverage.Channels in VIS, NIR, SWIR and the TIR window around 11 micrometers
Cloud optical depth3 - highLow-density cloud only.. Infrequent coverage.. Daylight only.VIS, NIR and SWIR channels
Cloud top height3 - highInfrequent coverage.TIR channels in the 11 micrometers window and the water vapour band around 6.3 micrometers (for emissivity) to estimate cloud top height from its temperature
Cloud top temperature2 - very highInfrequent coverage.TIR channels in the window around 11 micrometers and the water vapour band around 6.3 micrometers (for emissivity) to estimate cloud top height from its temperature
Cloud type2 - very highInfrequent coverage.Channels in VIS, NIR, SWIR and the TIR window around 11 micrometers
Fire fractional cover1 - primaryCloud sensitive.. Infrequent coverage.VIS and TIR channels
Fire radiative power5 - marginalCloud sensitive.. Infrequent coverage.TIR window channel(s) around 11 micrometers
Fire temperature5 - marginalCloud sensitive.. Infrequent coverage.TIR window channel(s) around 11 micrometers
Fraction of vegetated land1 - primaryCloud sensitive.. Daylight only.VIS, NIR and SWIR channels
Glacier cover3 - highCloud sensitive.. Long time for mapping.. Daylight only.VIS, NIR and SWIR channels, screening ice from clouds
Glacier topography4 - fairCloud sensitive.. Long time for mapping.. Daylight only.VIS channel(s) and steering capability both cross and along track for stereoscopy both in-orbit and between orbits
Ice sheet topography4 - fairCloud sensitive.. Long time for mapping.. Daylight only.VIS channel(s) and steering capability both cross and along track for stereoscopy both in-orbit and between orbits
Land cover1 - primaryCloud sensitive.. Daylight only.VIS, NIR and SWIR channels
Land surface temperature4 - fairCloud sensitive.. Infrequent coverage.TIR split window channels around 11 micrometers for water vapour correction
Land surface topography4 - fairCloud sensitive.. Long time for mapping.. Daylight only.VIS channel(s) and steering capability both cross and along track for stereoscopy both in-orbit and between orbits
Leaf Area Index (LAI)*2 - very highCloud sensitive.. Daylight only.. Infrequent coverage.VIS, NIR and SWIR channels
Normalised Difference Vegetation Index (NDVI)*2 - very highCloud sensitive.. Infrequent coverage.VIS and NIR channels
Photosynthetically Active Radiation (PAR)5 - marginalCloud sensitive.. Infrequent coverage.VIS channels, range undersampled
Sea surface temperature4 - fairCloud sensitive.. Infrequent coverage.TIR split window channels for water vapour correction
Short-wave cloud reflectance4 - fairInfrequent coverage.VIS, NIR and SWIR channels. Unsuitable dynamic range (saturation)
Snow cover1 - primaryCloud sensitive.. Infrequent coverage.. Daylight only.VIS, NIR and SWIR channels, enabling screening snow from clouds
Soil moisture at surface4 - fairCloud sensitive.. Index only.. Infrequent coverage.VIS and TIR window channels. Soil moisture inferred from thermal inertia
Soil type1 - primaryCloud sensitive.. Daylight only.VIS, NIR and SWIR channels
Integrated Water Vapour (IWV)2 - very highCloud sensitive.. Infrequent coverage.NIR and TIR channels around 940 nm, 6.3 micrometers and in the 11 micrometers split window
Upward short-wave irradiance at TOA5 - marginalSpectral interpolation needed.. Information on BRDF needed.. Infrequent coverage.VIS, NIR and SWIR channels
Vegetation type2 - very highCloud sensitive.. Daylight only.VIS, NIR and SWIR channels
Aerosol volcanic ash5 - marginalCloud sensitive.. Infrequent coverage.. Daylight only.VIS, NIR and SWIR channels
Aerosol volcanic ash Total Column5 - marginalCloud sensitive.. Infrequent coverage.. Daylight only.VIS, NIR and SWIR channels
Sea-ice cover2 - very highCloud sensitive.VIS, NIR (for contour enhancement), SWIR (for discrimination from clouds) and TIR channels