12 categories of ALOS study

  1. To evaluate sensor characteristics of PRISM and AVNIR-2 as well as quality of obtained image data.
  2. Geometric correction and inspection of obtained image data.
  3. To develop high-speed, highly accurate extract method of physical volume.


  1. Evaluate sensor characteristics of PRISM and image quality of obtained data.
  2. Geometric correction and inspection, and radiometric correction and inspection of obtained image data.
  3. Efforts to find more advanced analysis method using scattered microwave and SAR interference.

3. DEM Mapping

  1. Develop automatic producing method of DEM.
  2. Develop automatic producing method of Ortho-image for map data.
  3. Develop technology for efficient map update

4. Land Use and Land Cover Research
  1. te land cover categorization.
  2. Monitor changes of land use and vegetation due to urban and housing development

5. Disaster prevention and monitoring
  1. Earthquakes, diastrophism and volcano monitoring
  2. Forests fire, flooding
  3. Landslides, Slope failure, Ground sinking
  4. Oil spill due to tanker accidents
  5. Anticipation towards the disaster above and monitoring the impacts of the disaster

6. Geological features, Mineral Resources
  1. Geological research and mineral resource exploration using integrated PALSAR data into DEM, Ortho-image and data from other satellites.

7. Biological Resources

  1. Understand forests global mapping to analyze circulation mechanism of carbon and vegetation dynamics that play a major role for global warming.
  2. Deforestation for urbanization, firewoods and exportation, human activities such as biomass burning, forests fire, and alteration of forests and grasslands due to natural disaster of drought.
  3. Productivity and growth of farm, grasslands and forests, tree distribution of forests, planting status of farm products, monitoring and estimation of damage by blights and insects

8. Oceanic field
  1. Study on waves, monsoon, coastal current and sea ices.
  2. Figure out ocean dynamics.
  3. Monitoring land deformation due to coastal erosion and accumulation.
  4. Monitoring change of distribution and growth status of coral reef.
  5. Monitoring ocean pollution due to tanker accident or inflows of polluted river water, and study and research the influence on coastal fishery affected by red tide etc.

9. Snow and Ice
  1. Monitor wide range of snow cover and snow water analyzed PALSAR or
    AVNIR-2 data.
  2. Monitoring mountain glacier and distribution and lapse change of draft ice and sea ice.
  3. Understand the ice sheet mass balance and mountain variation in the South Pole.

10. Agriculture

  1. Understand and research on the estimation of changes regarding productivity, growth volume and crops on farm or grassland, and planting status of agricultural products.

11. Water Vapor / Water Resources
  1. Develop algorithms for measuring key parameters for water vapor estimation.
  2. Analyze land deformation and flow change due to soil erosion along the river, or accumulation.
  3. Analyze outflow change utilizing land use, land cover change or DEM.
  4. Analyze water pollution
  5. General water resource management in the areas where there is insufficient available data.

12. Geography
  1. Arrange Geographic Information System (GIS) integrated map data into statistic information.
  2. Study land management to establish arrangement plan and support management for urban facilities such as houses, trains, roads, water services.
  3. Study on the subject that is deeply related to human residing areas such as environment assessment, monitoring climate change in urban areas including heat island phenomenon
  4. Conservation Plan for important heritage
  5. Estimation and prevention strategy towards infectious diseases or parasite worm diseases using vegetation status and soil moisture data.

ALOS satellite snaps Europe

ESA has for the first time acquired and processed images sent by ALOS – Japan's four-tonne satellite dedicated to land-based Earth Observation – including views of Italy, The Netherlands and Norway.

ESA is supporting ALOS as a 'Third Party Mission', which means the agency is utilising its multi-mission ground segment of existing European facilities and expertise to acquire, process and distribute data from the satellite.

"We have received high-quality data from ALOS, and our team has worked extremely hard and done a great job acquiring and processing the images. We are very excited about the future data we will receive from ALOS and think they will be very beneficial to users," ESA’s Third Party Mission Manager Bianca Hoersch said.

ALOS captured the image of Naples, Italy, with its Advanced Visible and Near Infrared Radiometer type-2 (AVNIR-2), which is designed to chart land cover and vegetation in visible and near infrared spectral bands.

The images of The Netherlands and Norway were captured by the Phased Array type L-band Synthetic Aperture Radar (PALSAR) instrument – a microwave radar instrument that can acquire observations during both day and night and through any weather conditions.

The images were acquired on 28 April and 1 May 2006 at Kiruna Esrange and were processed at ESRIN, ESA’s Earth observation centre in Frascati, Italy.

In addition to these instruments, ALOS also carries the Panchromatic Remote-sensing Instrument of Stereo Mapping (PRISM), which can observe selected areas in three dimensions, down to a high 2.5-metre spatial resolution.

ALOS – delivered into a 700-kilometre polar orbit on 24 January 2006 from the Tanegashima Space Centre in Japan – is now in its nine-month Commissioning Phase.

Based on a cooperative agreement with the Japan Aerospace Exploration Agency (JAXA), ESA is hosting the ALOS European Data Node (ADEN), delivering near-real time and offline data to scientific and operational users across Europe and Africa. In order to deliver this, ESA has set up a Commissioning Phase Ground segment for ALOS with Kiruna Esrange, operated by the Swedish Space Corporation (SSC) as the downlink station.

Data from Kiruna is transferred electronically to ESRIN and is processed in a shared approach between ESRIN and the Neustrelitz Station, located in Germany, operated by the German Space Agency (DLR).

ESA will continue to test the ground segment chain from acquisition to archiving, processing and distribution with more regular downlinks scheduled to begin in late May. In addition to receiving data directly from ALOS, ESA will start to receive data offline from JAXA via media at the same time. The data volume is estimated to be around 200-250 Gigabytes daily, covering the ADEN zone.

When ALOS enters its Operational Phase, ESA will set up a larger ground segment with various acquisition stations and archives to provide optimal coverage over the ADEN zone. Operational ALOS data distribution from ESA will begin in November 2006.

An ESA Announcement of Opportunity for scientific use of ALOS data has already received 150 proposals, with 139 coming from ESA Member States, requesting a total of 26 000 ALOS products along with 14 000 products from ESA’s ERS-2 and Envisat satellites as well as other Third Party Missions.

"Regular Category-1 data access – requested by scientists for further research projects – will be open at reproduction cost to the scientific and pre-operational user community for proposal submission from July," Hoersch said.

Operational and commercial users will be able to receive ALOS data via commercial distribution schemes. ALOS data will also be available for Global Monitoring for Environment and Security (GMES), the joint initiative by ESA and the European Union to develop an independent environmental monitoring capability for Europe.


The Phased Array type L-band Synthetic Aperture Radar (PALSAR) is an active microwave sensor using L-band frequency to achieve cloud-free and day-and-night land observation. It provides higher performance than theJERS-1's synthetic aperture radar (SAR). Fine resolution in a conventional mode, but PALSAR will have another advantageous observation mode. ScanSAR, which will enable us to acquire a 250 to 350km width of SAR images (depending on the number of scans) at the expense of spatial resolution. This swath is three to five times wider than conventional SAR images. The development of the PALSAR is a joint project between JAXA and the Japan Resources Observation System Organization (JAROS).

PALSAR Characteristics

Mode Fine ScanSAR Polarimetric
(Experimental mode)*1
Center Frequency 1270 MHz(L-band)
Chirp Bandwidth 28MHz 14MHz 14MHz,28MHz 14MHz
Polarization HH or VV HH+HV or VV+VH HH or VV HH+HV+VH+VV
Incident angle 8 to 60deg. 8 to 60deg. 18 to 43deg. 8 to 30deg.
Range Resolution 7 to 44m 14 to 88m 100m
(multi look)
24 to 89m
Observation Swath 40 to 70km 40 to 70km 250 to 350km 20 to 65km
Bit Length 5 bits 5 bits 5 bits 3 or 5bits
Data rate 240Mbps 240Mbps 120Mbps,240Mbps 240Mbps
NE sigma zero *2 < -23dB (Swath Width 70km) < -25dB (Swath Width 60km) < -25dB < -29dB
S/A *2,*3 > 16dB (Swath Width 70km)
> 21dB (Swath Width 60km)
> 21dB > 19dB
Radiometric accuracy scene: 1dB / orbit: 1.5 d

Note: PALSAR cannot observe the areas beyond 87.8 deg. north latitude and 75.9 deg. south latitude when the off-nadir angle is 41.5 deg.
* 1 Due to power consumption, the operation time will be limited.
* 2 Valid for off-nadir angle 34.3 deg. (Fine mode),
34.1 deg. (ScanSAR mode),
21.5 deg. (Polarimetric mode)
* 3 S/A level may deteriorate due to engineering changes in PALSAR.

- Daichi, Advance Land Observing Satellite.

AVNIR-2 Sensor

The Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2) is a visible and near infrared radiometer for observing land and coastal zones. It provides better spatial land-coverage maps and land-use classification maps for monitoring regional environments. AVNIR-2 is a successor to AVNIR that was on board the Advanced Earth Observing Satellite (ADEOS), which was launched in August 1996.
Its instantaneous field-of-view (IFOV) is the main improvement over AVNIR. AVNIR-2 also provides 10m spatial resolution images, an improvement over the 16m resolution of AVNIR in the multi-spectral region. Improved CCD detectors (AVNIR has 5,000 pixels per CCD; AVNIR-2 7,000 pixels per CCD) and electronics enable this higher resolution. A cross-track pointing function for prompt observation of disaster areas is another improvement. The pointing angle of AVNIR-2 is +44 and - 44 degree.

AVNIR-2 Characteristics

Number of Bands
Band 1 : 0.42 to 0.50 micrometers
Band 2 : 0.52 to 0.60 micrometers
Band 3 : 0.61 to 0.69 micrometers
Band 4 : 0.76 to 0.89 micrometers
Spatial Resolution
10m (at Nadir)
Swath Width
70km (at Nadir)
Band 1 through 3 : >0.25
Band 4 : >0.20
Number of Detectors
Pointing Angle
- 44 to + 44 degree
Bit Length
8 bits

Note: AVNIR-2 cannot observe the areas beyond 88.4 degree north latitude and 88.5 degree south latitude.

- Daichi, Advance Land Observing Satellite.

PRISM Sensor

The Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) is a panchromatic radiometer with 2.5m spatial resolution at nadir. Its extracted data will provide a highly accurate digital surface model (DSM).

PRISM has three independent optical systems for viewing nadir, forward and backward producing a
stereoscopic image along the satellite's track. Each telescope consists of three mirrors and several CCD detectors for push-broom scanning. The nadir-viewing telescope covers a width of 70km; forward and backward telescopes cover 35km each.

The telescopes are installed on the sides of the optical bench with precise temperature control. Forward and backward telescopes are inclined +24 and -24 degrees from nadir to realize a base-to-height ratio of 1.0. PRISM's wide field of view (FOV) provides three fully overlapped stereo (triplet) images of a 35km width without mechanical scanning or yaw steering of the satellite. Without this wide FOV, forward, nadir, and
backward images would not overlap each other due to the Earth's rotation.

PRISM Characteristics

Number of Bands

1 (Panchromatic)

0.52 to 0.77 micrometers
Number of Optics

3 (Nadir; Forward; Backward)
Base-to-Height ratio

1.0 (between Forward and Backward view)
Spatial Resolution

2.5m (at Nadir)
Swath Width

70km (Nadir only) / 35km (Triplet mode)


Number of Detectors

28000 / band (Swath Width 70km)
14000 / band (Swath Width 35km)
Pointing Angle

-1.5 to +1.5 degrees
(Triplet Mode, Cross-track direction)
Bit Length

8 bits

Note: PRISM cannot observe areas beyond 82 degrees south and north latitude.

Observation Modes

Mode 1

Triplet observation mode using Forward, Nadir, and Backward views (Swath width is 35km)
Mode 2

Nadir (70km) + Backward (35km)
Mode 3

Nadir (70km)
Mode 4

Nadir (35km) + Forward (35km)
Mode 5

Nadir (35km) + Backward (35km)
Mode 6

Forward (35km) + Backward (35km)
Mode 7

Nadir (35km)
Mode 8

Forward (35km)
Mode 9

Backward (35km)

- Daichi, Advance Land Observing Satellite.

ALOS Characteristic

Launch Date
Jan. 24, 2006
Launch Vehicle
Launch Site
Tanegashima Space Center
Spacecraft Mass
Approx. 4 tons
Generated Power
Approx. 7 kW (at End of Life)
Design Life
3 -5 years
Sun-Synchronous Sub-Recurrent

Repeat Cycle: 46 days
Sub Cycle: 2 days

Altitude: 691.65 km (at Equator)

Inclination: 98.16 deg.
Attitude Determination Accuracy
2.0 x 10-4degree (with GCP)
Position Determination Accuracy
1m (off-line)
Data Rate
240Mbps (via Data Relay Technology Satellite)
120Mbps (Direct Transmission)
Onboard Data Recorder
Solid-state data recorder (90Gbytes)

- Daichi, Advance Land Observing Satellite.

About ALOS

ALOS Overview

The Japanese Earth observing satellite program consists of two series: those satellites used mainly for atmospheric and marine observation, and those used mainly for land observation. The Advanced Land Observing Satellite (ALOS) follows the Japanese Earth Resources Satellite-1 (JERS-1) and Advanced Earth Observing Satellite (ADEOS) and will utilize advanced land-observing technology. ALOS will be used for
cartography, regional observation, disaster monitoring, and resource surveying.

The ALOS has three remote-sensing instruments: the Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) for digital elevation mapping, the Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2) for precise land coverage observation, and the Phased Array type L-band Synthetic Aperture Radar (PALSAR) for day-and-night and all-weather land observation. In order to utilize fully the data obtained by these sensors, the ALOS was designed with two advanced technologies: the former is the high speed and large capacity mission data handling technology, and the latter is the precision spacecraft position and attitude determination capability. They will be essential to high-resolution remote sensing satellites in the next decade. ALOS have been successfuly launched on an H-IIA launch vehicle from the Tanegashima Space Center, Japan.

ALOS Objective

ALOS is one of the largest Earth observing satellites ever developed. Its objectives are:
  • To provide maps for Japan and other countries including those in the Asian-Pacific region (Cartography)
  • To perform regional observation for "sustainable development", harmonization between Earth environment and development (Regional Observation),
  • To conduct disaster monitoring around the world (Disaster Monitoring),
  • To survey natural resources (Resources Surveying),
  • To develop technology necessary for future Earth observing satellite (Technology Development)
- Daichi, Advance Land Observing Satellite.