# Michibiki 1R

> Japanese navigation satellite

**Wikidata**: [Q109255794](https://www.wikidata.org/wiki/Q109255794)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/QZS-1R)  
**Source**: https://4ort.xyz/entity/michibiki-1r

## Summary
Michibiki 1R (QZS-1R) is a Japanese navigation satellite launched on October 26, 2021, as a replacement for the original Michibiki 1 satellite. It operates as part of Japan's Quasi-Zenith Satellite System (QZSS) to provide enhanced GPS coverage over Japan and surrounding regions.

## Key Facts
- Launched on October 26, 2021, aboard an H-IIA rocket (H-IIA-44 configuration)
- Satellite catalog number: 49336, International Designator: 2021-096A
- Mass: 4,000 kg (launch mass) / 2,369.3 kg (dry mass)
- Dimensions: 5.405 m height × 2.869 m width × 2.359 m depth (solar array length)
- Manufacturer: Mitsubishi Electric
- Operator: Japan Aerospace Exploration Agency (JAXA)
- Part of the Quasi-Zenith Satellite System (QZSS) constellation
- Country of origin: Japan
- Provides navigation services for Japan and surrounding regions

## FAQs
### Q: What is Michibiki 1R's primary function?
A: Michibiki 1R is a navigation satellite that provides enhanced GPS coverage for Japan and surrounding regions as part of the Quasi-Zenith Satellite System (QZSS), improving positioning accuracy and reliability.

### Q: When was Michibiki 1R launched and what rocket was used?
A: Michibiki 1R was launched on October 26, 2021, aboard an H-IIA rocket (specifically the H-IIA-44 configuration) from Japan's Tanegashima Space Center.

### Q: How does Michibiki 1R differ from the original Michibiki 1?
A: Michibiki 1R is a replacement satellite for the original Michibiki 1, featuring upgraded technology and capabilities to continue providing navigation services for Japan's QZSS constellation.

## Why It Matters
Michibiki 1R plays a crucial role in Japan's national infrastructure by enhancing GPS navigation capabilities specifically for the Japanese archipelago and surrounding regions. As part of the QZSS constellation, it provides more accurate and reliable positioning data than standard GPS alone, which is essential for various applications including transportation, disaster management, agriculture, and autonomous systems. The satellite's design allows it to maintain a quasi-zenith orbit, meaning it appears almost directly overhead in Japan, providing stronger signals and better coverage in mountainous and urban areas where GPS signals might otherwise be obstructed. This system is particularly important for Japan's disaster resilience strategy, as it can provide critical positioning data even when ground-based infrastructure is compromised during natural disasters.

## Notable For
- First replacement satellite in Japan's QZSS constellation
- Enhanced navigation capabilities specifically optimized for Japanese geography
- Part of Japan's strategy for technological independence in satellite navigation
- Advanced solar array design with 18.901 m² surface area
- Successor to the original Michibiki 1, maintaining continuous QZSS service

## Body
### Technical Specifications
Michibiki 1R features a three-axis stabilized design with a launch mass of 4,000 kg and dry mass of 2,369.3 kg. The satellite measures 5.405 m in height, 2.869 m in width, and has a solar array length of 2.359 m. Its solar panels provide 18.901 m² of surface area for power generation.

### Mission Details
The satellite operates in a highly inclined, eccentric geosynchronous orbit that allows it to appear almost directly overhead in Japan for extended periods. This "quasi-zenith" orbit provides superior coverage compared to traditional geostationary satellites, particularly in mountainous and urban areas where line-of-sight to the sky is often obstructed.

### System Integration
As part of the QZSS constellation, Michibiki 1R works in conjunction with other navigation satellites to provide L1, L2, and L5 frequency signals compatible with GPS. This integration allows compatible receivers to use both GPS and QZSS signals simultaneously, improving accuracy and reliability.

### Operational Capabilities
The satellite provides several key services including:
- Standard Positioning Service (SPS)
- Quasi-Zenith Satellite Navigation System (QZSS) services
- Safety Confirmation Service (SCS)
- Disaster Management Support System (DMSS)

### Launch and Deployment
Launched from JAXA's Tanegashima Space Center, the H-IIA-44 rocket successfully placed Michibiki 1R into its target orbit. The launch marked the continuation of Japan's independent navigation satellite capabilities and demonstrated the reliability of the H-IIA launch vehicle for critical national infrastructure missions.

## References

1. [Source](https://space.skyrocket.de/doc_sdat/qzs-2.htm)
2. Jonathan's Space Report
3. [Source](https://qzss.go.jp/en/technical/qzssinfo/khp0mf0000000wuf-att/spi-qzs1r_a_220120.pdf)