HELSINKI — Japan’s flagship H3 rocket successfully launched the Michibiki 6 navigation satellite early Sunday, enhancing the country’s regional GPS capabilities.
The Mitsubishi Heavy Industries (MHI) H3 rocket lifted off at 3:30 a.m. Eastern (0830 UTC) Feb. 2 from Tanegashima Space Center.
Aboard was the 1,900-kilogram Michibiki 6 satellite, also known as the Quasi-Zenith Satellite System (QZS-6), for Japan’s navigation satellite system. The system aims to provide Japan with positioning, navigation and timing services, while increasing the accuracy and reliability of GPS services in the region.
Michibiki 6 will be placed at 90.5 degrees East in the geostationary belt, 35,786 kilometers above the equator.
The first Michibiki spacecraft for a four-satellite system was launched in 2010. An 11-satellite system, to provide redundancy, is being considered, according to a 2024 policy document from the Cabinet Office of the Government of Japan.
The 63-meter-long H3 comes in configurations with no solid rocket boosters, two SRBs or four SRBs for higher payload needs. The latter pair of configurations can also utilize an elongated payload fairing.
The launcher’s inaugural launch in March 2023, after numerous delays, suffered a second stage engine failure, leading controllers to issue a destruct command to destroy the stage and its ALOS-3 payload.
Since then, it has had a successful run of launches, most recently launching the Kirameki 3 communications satellite for defense purposes in November last year.
The expendable rocket was designed to be more cost-effective and therefore competitive on the international commercial launch market.
The H3 received a boost last year with the announcements that the H3 will launch an asteroid mission for the United Arab Emirates, currently scheduled for 2028, while Eutelsat signed a contract to use multiple H3 rockets from 2027.
The launch was Japan’s first of 2025. Meanwhile, the Resilience lander from Japanese private space exploration firm ispace launched Jan. 15 on a SpaceX Falcon 9 rocket. The lander is currently in Earth orbit and will gradually raise its orbit as part of a low-energy journey to the moon. A landing attempt is expected in around four months’ time.
Japanese launch activities for Japanese fiscal year 2025 (running April 2025 to March 2026) could include the last flight of the H-2A workhorse rocket—to be replaced by the H3—carrying the GOSAT-3 satellite to detect greenhouse gases, the first flight of the HTV-X uncrewed expendable cargo spacecraft to the International Space Station (ISS), and a launch of the Epsilon S.
A first flight of the H3-24 variant, which features four SRSs, could take place in 2025. That variant will have the highest payload capacity to geosynchronous transfer orbit of the H3 series at 8,800 kilograms.
