DESIS, the DLR Earth Sensing Imaging Spectrometer, was developed by the German Aerospace Center and Teledyne Brown Engineering. DESIS is a hyperspectral imaging spectrometer covering the Visible and Near Infrared optical spectral region (400-1000nm). Bands are natively spaced at ~2.55nm. The Ground Sample Distance or pixel size is ~30m and the image tile size is 30km by 30km. DESIS resides on the MUSES (Multi-User System for Earth Sensing) platform on board the International Space Station. MUSES is inertially stabilized and can be precision tasked to your AOI. DESIS represents a large leap forward in having a reliable, well calibrated, high SNR, hyperspectral sensor in space.
Operating on the ISS presents opportunities and challenges. The ISS provides the advantages of a fast, low cost route to space, instrument return, and opportunity to repair the instrument since it is a manned platform. Imaging is dependent on the ISS orbit and space-based activities, but covers 90% of the populated earth and has frequent cover of the tropics—areas where quality hyperspectral data is limited because of persistent cloud cover.
Teledyne Brown Engineering is the Commercial and Government distributor of DESIS data and the developer of the MUSES platform. NASA and Teledyne Brown Engineering have a cooperative agreement to provide NASA unlimited data. More information can be found on the
Access page . Data can be browsed at
Teledyne.tcloudhost.com.
|
Parameter |
DESIS values (Commissioning Phase) |
|
Orbit (type, local time at equator, inclination, altitude, period, repeat cycle) |
not Sun-synchronous, various, 51.6°, 405 ± 5 km, 93 min, no repeat cycle |
|
Coverage |
55° N to 52° S |
|
Tilt (across-track, along-track) |
-45° to +5°, -40° to +40° by MUSES and DESIS |
|
Sensor pointing |
±15° along-track to enable BRDF or Stereo acquisitions |
|
Spectral coverage |
402 nm to 1000 nm |
|
Number of spectral channels |
235 (no binning)
118 (binning 2)
79 (binning 3)
60 (binning 4)
|
|
Defective spectral channels |
Bands 1 – 7 (no binning)
Bands 1 – 4 (binning 2)
Bands 1 – 3 (binning 3)
Bands 1 – 2 (binning 4)
|
|
Spectral sampling resolution |
2.55 nm (w/o binning); ~10.2 nm (binning 4) |
|
Full Width Half Maximum (FWHM) |
~3.5 nm (w/o binning); ~10.0 nm (binning 4) |
|
Radiometric resolution |
12 bits + 1 bit gain |
|
Radiometric accuracy |
+/-10% (based on on-ground calibration and with support of inflight radiometric calibration) |
|
Radiometric linearity |
99% |
|
Swath |
30 km |
|
Spatial resolution, pixels |
30 m, 1024 pixels (@400 km) |
|
Geometric accuracy |
~20 m with GCPs 1
~300 m - 400 m w/o GCPs
|
|
MTF @ Nyquist |
30%-40% based on on-ground calibration / static MTF without smearing effects / wavelength depending |
|
Signal-to-Noise ratio (albedo 0.3 @ 550 nm) |
195 (w/o binning)
386 (4 binning)
(based on on-ground calibration)
|
|
Dark/Read noise (electrons) |
30-60e- (global shutter)
15-30e- (rolling shutter)
|
|
Quantum scale equivalent (e-/DN) |
0.04 e-/DN |
|
Max frame rate |
235Hz (@235 spectral lines, rolling shutter)
117Hz (@235 spectral lines, global shutter)
|
|
Solar zenith angle restrictions
(for L2A level processing)
|
> 55° produces reduced quality L2A product
> 65° produces low quality L2A product
> 70° not processible to L2A
|
1 with respect to global reference Landsat ETM+ PAN with GSD 14 m
