# ALOS

> Japanese synthetic-aperture radar satellite launched in 2006

**Wikidata**: [Q49480](https://www.wikidata.org/wiki/Q49480)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Advanced_Land_Observing_Satellite)  
**Source**: https://4ort.xyz/entity/alos

## Summary
ALOS is a Japanese synthetic-aperture radar satellite launched in 2006 that revolutionized Earth observation with its advanced L-band SAR capabilities. Officially known as the Advanced Land Observing Satellite and also called Daichi, it operated for over five years, collecting valuable data for environmental monitoring and disaster management.

## Key Facts
- ALOS (Advanced Land Observing Satellite) is a Japanese synthetic-aperture radar satellite launched on January 24, 2006
- The satellite was operated by the Japan Aerospace Exploration Agency (JAXA)
- ALOS was manufactured by NEC, Toshiba, and Mitsubishi Electric corporations
- It had a launch weight of 4,000 kg and a dry weight of 3,820 kg
- ALOS operated from January 2006 until May 12, 2011, exceeding its 3-year design life
- It was launched using an H-IIA rocket from Yoshinobu Launch Complex Launch Pad 1
- ALOS carried the Phased Array L-band Synthetic Aperture Radar instrument
- The satellite operated in a Sun-synchronous orbit

## FAQs
### Q: What was the primary purpose of ALOS?
A: ALOS was designed for advanced land observation and Earth monitoring, utilizing its synthetic aperture radar capabilities to gather detailed imagery for environmental research, disaster management, and mapping applications.

### Q: When was ALOS decommissioned and why?
A: ALOS was officially decommissioned on May 12, 2011, after experiencing a voltage drop on April 22, 2011, that led to a loss of signal, despite its service life exceeding the original design specifications.

### Q: How does ALOS differ from its successor ALOS-2?
A: ALOS-2 is the successor satellite launched in 2014 with enhanced SAR capabilities, while ALOS was the pioneering Japanese synthetic-aperture radar satellite with its L-band SAR instrument that operated from 2006-2011.

## Why It Matters
ALOS represented a significant advancement in Japanese remote sensing technology, providing high-resolution Earth observation data that proved invaluable for disaster response, environmental monitoring, and agricultural assessment. Its 5.3-year service life demonstrated the reliability of Japanese space technology and established Japan as a major player in Earth observation satellites. The data collected by ALOS has been used globally for applications ranging from mapping deforestation to monitoring natural disasters, contributing significantly to scientific understanding and practical applications of remote sensing technology.

## Notable For
- Being Japan's first advanced synthetic-aperture radar satellite with L-band capabilities
- Operating for 5.3 years, significantly exceeding its 3-year design life
- Providing crucial Earth observation data for disaster response and environmental monitoring
- Featuring a Phased Array L-band Synthetic Aperture Radar instrument for high-resolution imaging
- Serving as the predecessor to ALOS-2, which launched in 2014 with enhanced capabilities

## Body
### Technical Specifications
ALOS (Advanced Land Observing Satellite), also known as Daichi, is a Japanese synthetic-aperture radar satellite with a mass of 4,000 kg at launch and 3,820 kg dry weight. The satellite was powered by a single solar array generating 7,000 watts. It operated in a Sun-synchronous orbit, which allowed for consistent imaging conditions over the Earth's surface.

### Development and Manufacturing
The satellite was manufactured by a consortium of major Japanese corporations: NEC, Toshiba, and Mitsubishi Electric. Mitsubishi Heavy Industries served as the launch contractor, while the Japan Aerospace Exploration Agency (JAXA) operated the satellite throughout its mission.

### Mission Timeline
ALOS was launched on January 24, 2006, at 01:33 UTC from Yoshinobu Launch Complex Launch Pad 1 using an H-IIA rocket. Despite being designed for a 3-year service life, the satellite operated successfully for 5.3 years until April 22, 2011, when a voltage drop caused a loss of signal. The satellite was officially decommissioned on May 12, 2011.

### Scientific Instrumentation
The satellite's primary instrument was the Phased Array L-band Synthetic Aperture Radar (PALSAR), which provided high-resolution radar imagery for Earth observation. This instrument enabled ALOS to collect data day and night, regardless of weather conditions, making it particularly valuable for disaster monitoring and environmental assessment.

### Legacy and Successor
ALOS established Japan as a leader in Earth observation technology with its SAR capabilities. The success of ALOS led to the development of ALOS-2, launched in 2014, which features enhanced SAR capabilities and improved resolution for advanced Earth observation applications.

## Schema Markup
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  "@type": "Thing",
  "name": "ALOS",
  "description": "Japanese synthetic-aperture radar satellite launched in 2006",
  "url": "https://www.satnavi.jaxa.jp/ja/project/alos/",
  "sameAs": [
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  "countryOfOrigin": "Japan",
  "manufacturer": ["NEC", "Toshiba", "Mitsubishi Electric"],
  "operator": "Japan Aerospace Exploration Agency",
  "launchDate": "2006-01-24",
  "launchVehicle": "H-IIA",
  "orbitType": "Sun-synchronous orbit",
  "serviceStartDate": "2006-01-24",
  "serviceEndDate": "2011-05-12"
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## References

1. [Source](https://directory.eoportal.org/satellite-missions/alo)
2. Jonathan's Space Report
3. [Source](https://space.oscar.wmo.int/satellites/view/alos)
4. [Source](https://space.skyrocket.de/doc_sdat/alos.htm)
5. Freebase Data Dumps. 2013
6. [Source](https://www.space.com/11653-japanese-satellite-declared-dead-daichi.html)
7. [Source](http://www.jaxa.jp/press/2011/05/20110512_daichi_e.html)