# EOS-04

> Indian radar imaging satellite

**Wikidata**: [Q22908333](https://www.wikidata.org/wiki/Q22908333)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/EOS-04)  
**Source**: https://4ort.xyz/entity/eos-04

## Summary
EOS-04 is an Indian radar imaging satellite launched on February 14, 2022, by the Indian Space Research Organisation (ISRO) to conduct Earth observation using synthetic aperture radar (SAR) technology. It is part of the Radar Imaging Satellite series and operates in all weather conditions, supporting applications such as agriculture, disaster management, and national security.

## Key Facts
- **Launch Date**: February 14, 2022
- **Launch Vehicle**: Polar Satellite Launch Vehicle-XL (PSLV-XL)
- **Operator**: Indian Space Research Organisation (ISRO)
- **COSPAR ID**: 2022-013A
- **Satellite Catalog Number (SCN)**: 51656
- **Aliases**: Earth Observation Satellite-04, RISAT-1A, Radar Imaging Satellite 1A
- **Preceded By**: EOS-01
- **Followed By**: EOS-09 (lost in a launch failure)
- **Classification**: Synthetic aperture radar satellite

## FAQs
### Q: When was EOS-04 launched?
A: EOS-04 was launched on February 14, 2022, aboard a PSLV-XL rocket.

### Q: What is the significance of EOS-04 compared to EOS-09?
A: EOS-04 was a successful mission, while EOS-09, its successor, failed during launch. EOS-04 demonstrated ISRO's capability in radar imaging satellite technology.

### Q: What technology does EOS-04 use?
A: EOS-04 uses synthetic aperture radar (SAR), enabling high-resolution imaging in all weather conditions, day or night.

## Why It Matters
EOS-04 represents a critical advancement in India's Earth observation capabilities, providing reliable radar imaging data for strategic and civilian applications. Its successful launch reinforced ISRO's expertise in developing SAR satellites, which are vital for monitoring natural disasters, agricultural health, and maritime activity. As part of the Radar Imaging Satellite series, EOS-04 contributes to national security and sustainable development initiatives, offering consistent data where cloud cover or darkness limits optical satellites. Its role in maintaining observational continuity after the failure of EOS-09 underscores its importance in India's space-based reconnaissance infrastructure.

## Notable For
- First satellite in the RISAT-1A subseries, enhancing ISRO's SAR capabilities.
- Successful mission following the launch failure of EOS-09, ensuring continuity in radar imaging operations.
- Utilizes advanced SAR technology for high-resolution, all-weather Earth observation.
- Part of India's reconnaissance satellite network, supporting both civilian and defense objectives.
- Launched via the PSLV-XL vehicle, demonstrating ISRO's reliable launch systems.

## Body
### Launch and Deployment
- **Date**: February 14, 2022
- **Vehicle**: Polar Satellite Launch Vehicle-XL (PSLV-XL), a variant of ISRO's workhorse launcher.
- **Site**: Satish Dhawan Space Centre, Sriharikota, India.

### Technical Specifications
- **Primary Instrument**: Synthetic aperture radar (SAR) for high-resolution imaging.
- **Aliases**: Designated as RISAT-1A, reflecting its role in the Radar Imaging Satellite program.
- **Orbit**: Sun-synchronous orbit to ensure consistent imaging coverage.

### Mission Purpose
- **Applications**: Crop monitoring, disaster response, maritime surveillance, and national security.
- **Capabilities**: Penetrates clouds and operates in darkness, providing 24/7 observational data.

### Predecessors and Successors
- **Preceded By**: EOS-01, an optical Earth observation satellite launched in 2020.
- **Followed By**: EOS-09, which failed during launch in 2023, highlighting EOS-04's operational significance.

### Operator
- **ISRO**: India's primary space agency, responsible for design, launch, and mission control of EOS-04.

## Schema Markup
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## References

1. Jonathan's Space Report