H-IIA 202 | GOSAT-GW (Ibuki GW)
H-IIA • H-II
📝 Mission Description
Japan's H-IIA Rocket Set to Launch GOSAT-GW: Advancing Climate Monitoring from Space
On June 28, 2025, Japan's space agency, JAXA, is scheduled to launch the H-IIA 202 mission from the Tanegashima Space Center, carrying the GOSAT-GW satellite. This endeavor, also known as Ibuki GW or formerly GOSAT 3, represents a pivotal step in Earth's environmental observation, building on Japan's legacy of satellite technology to tackle global warming and climate variability.
At the heart of the mission are GOSAT-GW's dual objectives: monitoring greenhouse gases and observing the water cycle. The satellite will track key atmospheric components like carbon dioxide, methane, and carbon monoxide with unprecedented precision, aiding Japan's Ministry of the Environment and the National Institute for Environmental Studies (NIES) in assessing human-induced emissions and natural carbon sinks. Its payload includes advanced spectrometers and imaging sensors capable of high-resolution measurements, enabling the detection of greenhouse gas concentrations at a global scale. Complementing this, the water-cycle observation component, managed by JAXA, will monitor precipitation, soil moisture, and ocean salinity using microwave radiometers and scatterometers. These capabilities allow for integrated data on how water vapor and precipitation patterns interact with greenhouse gases, providing insights into phenomena like extreme weather events. By combining these functions, GOSAT-GW enhances predictive models for climate change, potentially improving disaster preparedness in vulnerable regions.
The launch vehicle, the H-IIA rocket, is a reliable workhorse in Japan's space program. Developed by Mitsubishi Heavy Industries in collaboration with JAXA, the H-IIA stands approximately 53 meters tall and weighs about 285 tons at liftoff in its standard configuration. It features a two-stage design: the first stage powered by a single LE-7A liquid hydrogen/liquid oxygen engine, supplemented by two or four solid rocket boosters depending on payload requirements, and a second stage driven by the LE-5B engine. For the H-IIA 202 variant, it offers a payload capacity of up to 4 tons to geostationary transfer orbit or 10 tons to low Earth orbit, making it versatile for scientific missions like GOSAT-GW. Technical innovations include cryogenic propulsion systems that provide high thrust efficiency, with the rocket's guidance system ensuring precise orbital insertion through inertial navigation and GPS integration.
The H-IIA's performance history underscores its dependability. Since its inaugural flight in 2001, the
ℹ️ Official Details
GOSAT-GW (Greenhouse Gases Observing Satellite Greenhouse gases and Water cycle), also known as Ibuki GW and formerly known as GOSAT 3, is JAXA's next generation satellite to monitor the greenhosue gases like carbon dioxide in the Earth's atmosphere. It is the follow on to the GOSAT 2 (Ibuki 2) and GCOM-W (Shizuku) missions.
GOSAT-GW will have two missions: greenhouse gases observation for Japan's Ministry of the Environment and the National Institute for Environmental Studies (NIES), and water-cycle observation for JAXA. By developing the GOSAT-GW satellite, Mitsubishi Electric will contribute to measures for preventing disasters attributed to global warming and climate change, and to advance scientific and technological methods that enable more accurate prediction of climate change.
In December 2013, Mitsubishi Electric (MELCO) was selected as the prime contractor for the spacecraft and the instruments.
🎯 Post-Launch Analysis
The H-IIA 202 mission, launched on June 28, 2025, successfully placed the GOSAT-GW (Ibuki GW) satellite into orbit, marking a significant achievement for JAXA. The rocket performed flawlessly, ensuring precise orbital insertion and payload deployment. GOSAT-GW, designed to monitor greenhouse gases and water cycles, builds on the legacy of GOSAT 2 and GCOM-W, with Mitsubishi Electric as the prime contractor delivering robust spacecraft and instrumentation. Key engineering outcomes include validated design and operational reliability, critical for dual-mission objectives supporting Japan’s Ministry of the Environment, NIES, and JAXA. This success reinforces the H-IIA’s dependability and sets a strong foundation for future environmental monitoring missions. The data from GOSAT-GW is expected to enhance global warming disaster prevention and climate change prediction, paving the way for advanced scientific insights and technological innovations in Earth observation.