Advanced Land Observing Satellite

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Advanced Land Observing Satellite (ALOS)
Type: Earth observation satellite
Country: JapanJapan Japan
Operator: Japan Aerospace Exploration AgencyJAXA JAXA
COSPAR-ID : 2006-002A
Mission dates
Dimensions: 4 t
Begin: January 24, 2006
Starting place: Tanegashima Space Center
Launcher: H-II A F8
Status: April 22, 2011: failure
Orbit data
Track height: 691.65 km
Orbit inclination : 98.16 °

The Advanced Land Observation Satellite ( German  advanced land observation satellite ), short ALOS , after starting renamed Daichi ( 'earth', earth '), a Japanese earth observation satellite , the Earth in a sun-synchronous orbits orbit. It provides data for cartography , environmental protection and disaster management . With ALOS, Japan participates in the International Charter on Space and Natural Disasters .

For unknown reasons, the power supply failed on April 22, 2011 and the satellite could no longer be addressed. The follow-up mission ALOS 2 was launched on May 24, 2014.

Data

The energy supply is 7 kW ( EOL ), so a service life of 3 to 5 years is planned. The satellite flies over the same locations in a cycle of 3 days. The position control accuracy is specified with ground control points 2.0 × 10 −4 ° , the orbit position accuracy should be 1 m offline. The data obtained by the optics are transferred to an onboard data memory with 90 Gb, a solid-state data recorder is used . When transmitting via Data Relay Technology Satellite , a data transmission rate of 240 Mbps is achieved; direct transmission does half.

equipment

The satellite has 3 instruments on board:

  • PRISM for stereo recordings
    - Panchromatic remote-sensing instrument for stereo mapping
    • Spectral band 0.52 - 0.77 μm
    • Number of optics: 3 (Nadir / Forward / Backward)
    • Width-height ratio: 1.0 (Forward / Backward)
    • S / N :> 70 = 18 dB
    • MTF:> 0.2
    • Local resolution on the ground: 2.5 m
    • Swath width: 35 km (Triplet mode), 70 km (Nadir Only, Wide swath mode)
    • Pointing angle ± 1.5 deg (triplet mode)
  • the radiometer AVNIR-2
    - Advanced Visible and Near Infrared Radiometer Type 2
    • Spectral band (μm) Band1: 0.42 - 0.50, Band2: 0.52 - 0.60, Band3: 0.61 - 0.69, Band4: 0.76 - 0.89
    • S / N:> 200 (23 dB)
    • MTF:> 0.2
    • Resolution: 10 m (with Nadir Pointing)
    • Swath Latitude: 70 km (at Nadir Pointing)
    • Pointing angle: ± 44 deg.
  • the L-band radar PalSAR
    - Phased Array L-Band Synthetic Aperture Radar
    • in high resolution mode:
      • Frequency : L-band (1.27 GHz, corresponding to 23.6 cm wavelength)
      • Polarization HH, VV, HH&HV, VV&VH
      • Resolution: 10 m
      • Swath Width: 70 km
      • Off-nadir angle: 10-51 °
    • in ScanSAR mode:
      • Frequency: L-band (1.27 GHz)
      • Polarization: HH, VV
      • Resolution: 100 m
      • Swath Latitude: 250-350 km
      • Off-nadir angle: 10-51 °

Individual evidence

  1. ↑ Japan's ALOS Craft Hit by Power Glitch. In: SpaceNews. April 11, 2011, accessed July 30, 2016 .
  2. ↑ Thomas Weyrauch: Japanese Earth observation satellite ALOS 2 launched. raumfahrer.net, May 24, 2014, accessed on May 26, 2014 .

Web links