# Michibiki 2

> Japanese navigation satellite

**Wikidata**: [Q45977820](https://www.wikidata.org/wiki/Q45977820)  
**Source**: https://4ort.xyz/entity/michibiki-2

## Summary
Michibiki 2 is a Japanese navigation satellite launched on June 1, 2017, as part of Japan's Quasi-Zenith Satellite System (QZSS) to enhance GPS coverage in the Asia-Oceania region. It was built by Mitsubishi Electric and launched aboard an H-IIA rocket from Tanegashima Space Center. The satellite operates in a highly inclined geosynchronous orbit to provide stable positioning signals over Japan.

## Key Facts
- Launched on June 1, 2017, aboard H-IIA-34 rocket (launch vehicle serial H-IIA)
- Satellite designation: QZS-2 (Quasi-Zenith Satellite 2), also known as Michibiki 2
- Manufacturer: Mitsubishi Electric Corporation
- Operator: Japan Aerospace Exploration Agency (JAXA)
- Launch mass: 4,000 kg (dry mass: 2,324.2 kg)
- Dimensions: 6.2 meters in length, 2.4 meters in width
- Solar array span: 19 meters
- Power generation: 2.85 kW
- Orbit: Highly inclined geosynchronous orbit (QZO)
- International Designator: 2017-028A
- Satellite Catalog Number: 42738

## FAQs
### Q: What is Michibiki 2's purpose?
A: Michibiki 2 is part of Japan's QZSS constellation designed to enhance GPS coverage in urban canyons and mountainous terrain where GPS signals are often blocked. It provides more accurate positioning and timing signals specifically for the Asia-Oceania region.

### Q: How does Michibiki 2 differ from GPS satellites?
A: Unlike GPS satellites in medium Earth orbit, Michibiki 2 operates in a highly inclined geosynchronous orbit that keeps it almost directly overhead Japan for extended periods. This provides stronger signals in areas where GPS is weak, such as urban areas with tall buildings.

### Q: Who operates Michibiki 2?
A: The Japan Aerospace Exploration Agency (JAXA) operates Michibiki 2 in collaboration with the Cabinet Office of Japan. The system is part of Japan's broader effort to ensure reliable satellite navigation independent of GPS.

## Why It Matters
Michibiki 2 represents a critical component of Japan's strategy to ensure reliable satellite navigation for its citizens and industries. In a country with dense urban areas, mountainous terrain, and frequent natural disasters, GPS signals can be unreliable or completely blocked. By providing a complementary navigation system that maintains strong signals over Japan, Michibiki 2 enhances everything from smartphone navigation to emergency response systems and autonomous vehicle operations. The satellite's highly inclined orbit ensures it remains almost directly overhead Japan for extended periods, providing stronger signals than traditional GPS satellites can achieve in challenging environments. This capability is particularly valuable for disaster response, where accurate positioning can mean the difference between life and death. As part of the four-satellite QZSS constellation, Michibiki 2 helps Japan achieve technological independence in critical infrastructure while also contributing to global navigation capabilities.

## Notable For
- First QZSS satellite to feature enhanced signal structure for improved urban and mountainous reception
- Operates in a unique highly inclined geosynchronous orbit that keeps it almost directly overhead Japan
- Provides both GPS augmentation and standalone positioning services for the Asia-Oceania region
- Features advanced atomic clock technology for precise timing signals
- Part of Japan's strategy to ensure reliable navigation during GPS outages or interference

## Body
### Technical Specifications
Michibiki 2 was constructed by Mitsubishi Electric Corporation using their DS2000 satellite bus. The spacecraft measures 6.2 meters in length and 2.4 meters in width, with a solar array span of 19 meters when deployed. The satellite generates 2.85 kW of power through its solar panels and uses advanced thermal control systems to maintain operational temperatures in the harsh space environment.

### Launch and Orbital Characteristics
The satellite launched on June 1, 2017, at 23:17 UTC from the Yoshinobu Launch Complex at Tanegashima Space Center. The H-IIA-34 rocket successfully placed Michibiki 2 into its target orbit. The spacecraft operates in a highly inclined geosynchronous orbit (QZO) with an orbital period of approximately 24 hours, but with an inclination that causes it to trace a figure-eight pattern in the sky when viewed from Earth. This unique orbit ensures the satellite remains almost directly overhead Japan for extended periods, providing stronger signals than traditional GPS satellites.

### Navigation Capabilities
Michibiki 2 broadcasts multiple navigation signals including L1C/A, L1C, L2C, and L5 bands, compatible with both GPS and GLONASS systems. The satellite provides three types of services: Centimeter-Level Augmentation Service (CLAS) for high-precision applications, Quasi-Zenith Satellite System Standard Service (QZS SS) for general positioning, and Safety Confirmation Service (SCS) for disaster response. The satellite's atomic clocks provide timing accuracy within nanoseconds, essential for precise positioning calculations.

### System Integration
As the second satellite in the QZSS constellation, Michibiki 2 works in conjunction with QZS-1 (launched in 2016) and subsequent satellites to provide continuous coverage over Japan. The system uses a minimum of four satellites to ensure at least one is always positioned to provide optimal coverage. The constellation provides enhanced GPS signals that are more resistant to multipath interference and can penetrate urban canyons and mountainous terrain more effectively than standard GPS signals.

### Applications and Impact
Michibiki 2's signals support a wide range of applications including automotive navigation, smartphone positioning, precision agriculture, construction surveying, and disaster response. The satellite's enhanced signals are particularly valuable in Japan's dense urban areas like Tokyo, where traditional GPS signals are often blocked by tall buildings. The system also provides critical backup navigation capabilities in case of GPS outages, which is particularly important for Japan's transportation and emergency response infrastructure. The satellite's Safety Confirmation Service can broadcast emergency information to users in affected areas during natural disasters, providing both positioning and critical communication capabilities.

## 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-qzs2_c.pdf)