Our Team

As a former US Army Intelligence Officer in Afghanistan, he saw how technology can transform daily life in the most remote and underserved areas. That experience drives his mission to make space more accessible, not just for exploration, but as a powerful tool to improve life on Earth. At Letara, he brings deep technical expertise and a clear vision for building the propulsion systems that will make that future possible.

He has independently developed, patented, and brought to market a groundbreaking low-power ignition system alongside advanced hybrid rocket technologies—ranging from erosion-resistant nozzles to next-generation 3D-printed fuels. In 2020, he co-founded his company with the mission to create globally competitive space solutions from Hokkaido and help retain top talent in the region. Today, his work focuses on advancing plastic-based hybrid propulsion systems for both satellites and launch vehicles, strengthening Japan’s presence in the international space industry.

field worldwide. He is the inventor of the CAMUI-type hybrid rocket and has led the development of multiple propulsion breakthroughs, including axial-injection end-burning engines and low-concentration hydrogen peroxide systems.

After earning his PhD from the University of Tokyo, Dr. Nagata began his career in the aerospace divisions of major Japanese companies, including IHI and Nissan Motor Co., where he worked on advanced propulsion technologies.

In 2020, he cofounded Letara to bring hybrid propulsion innovation into commercial space applications. As CSO, he continues to provide scientific leadership and technical guidance, supporting the company’s mission to build safer, more affordable, and sustainable access to space.

licensed legal professional under Japan’s judicial system, with expertise in company registration, compliance, and governance.

Before joining Letara, Keisuke also worked at Persol, gaining valuable experience in corporate operations and HR. Passionate about growing the space industry in Hokkaido, he is dedicated to building the legal and financial infrastructure needed for innovative startups like Letara to thrive.

clear conviction: hybrid propulsion is the most promising path to fast, affordable, and reliable access to space.

Fully bilingual in Japanese and English, Toku leverages his unique background spanning government, major defense contractors, and space manufacturers to rapidly scale Letara’s operations in both Japan and international markets. His deep understanding of strategy, policy, and commercialization enables Letara to build lasting partnerships and drive innovation across the global space ecosystem.

He has led key initiatives in small rocket development, microgravity experiments, satellite programs, and joint projects with U.S. commercial space companies.

Under his leadership, Uematsu Electric operates one of Japan’s largest commercial rocket testing facilities. With his direct support, Letara is able to rapidly design, build, and test high-thrust hybrid engines at a pace unmatched by its peers. His infrastructure and technical collaboration play a critical role in accelerating the development of next-generation propulsion systems in Japan.