Japanese rocket startup Interstellar raises another $129.7 million in private investment capital

The Japanese rocket startup Interstellar announced late last week that it has successfully raised another $129.7 million in private investment capital, bringing its total available cash to $287.7 million.

Interstellar’s Series F round represents one of the largest fundraising to date by a privately held space startup in Japan2, bringing Interstellar’s cumulative funding to 44.6 billion JPY (287.7 million USD). The round, led by Woven by Toyota, raised 14.8 billion JPY (95.5 million USD) through a third-party allotment of preferred shares in an up-round.

In addition, the company secured 5.3 billion JPY (34.2 million USD) in debt financing from financial institutions, including 1.8 billion JPY (11.6 million USD) in loan facilities with stock acquisition rights provided by the Japan Finance Corporation. Alongside the fundraising, secondary transactions with existing shareholders were also conducted to optimize the company’s capital structure. Nomura Securities provided advisory support in this series, including the introduction of several potential investors, some of which resulted in fundraising.

Interstellar was one of the earliest rocket startups, first attempting a suborbital launch in 2018. After that launch failed it then disappeared for almost five years to suddenly reappear last year with major funding from Toyota and other sources.

It had previously hoped to complete the first launch of its Zero orbital rocket in 2025. At the moment however the company has set no new launch date, though it has announced that it has seven customer payloads for that launch.

Rocket startup Interstellar receives another grant from Japan

The Rocket startup Interstellar announced on February 21, 2025 that Japan’s program to encourage commercial space has awarded it a new $9.3 million grant, bringing the total amount the company has received to approximately $53 million.

The SBIR is a 3 phased governmental program aimed to promote the implementation of advanced technologies developed by startups in Japan. Interstellar was selected in September 2023 under the space section focused on the “Development and Demonstration of Private Launch Vehicles” were the company received up to ¥2 billion [$13.3 million] in funding for Phase 1. After passing the review for Phase 2 in September 2024, another maximum of ¥4.6 billion [$30.8 million] were awarded.

In addition, in early January Toyota invested $44 million in this startup.

This story indicates that the Japanese government is finally moving to encourage private commercial space. It had announced this grant program in late 2023, but its bureaucracy had initially seemed reluctant to issue grants. This appears to be finally changing.

Interstellar is in itself an interesting story. Five years ago it appeared to be aggressively building its Zero rocket. It then disappeared. I figured its investment capital had dried up and the company had shut down. It seems it has now been reborn.

Interstellar suborbital launch ends in failure

Capitalism in space: A suborbital launch attempt today by Interstellar, a private Japanese smallsat rocket company, failed one minute into flight, with the rocket falling into the sea.

It apparently failed at about 12 kilometers elevation, when it began tumbling. I have embedded the video of the launch below the fold, cued to just before liftoff.

This was their fifth launch attempt. Only the third launch reached their target altitude of 100 kilometers.
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Paper extolling the benefits from interstellar spaceflight

This guy is thinking ahead: a paper extolling the scientific benefits of interstellar space travel (published in a 2009 issue of the Journal of the British Interplanetary Society) was made available today on the Los Alamos astro-ph website. Fun quote from the abstract:

Significant benefits are identified in the fields of interstellar medium studies, stellar astrophysics, planetary science and astrobiology. In the latter three areas the benefits would be considerably enhanced if the interstellar vehicle is able to decelerate from its interstellar cruise velocity to rest relative to the target system. Although this will greatly complicate the mission architecture, and extend the overall travel time, the scientific benefits are such that this option should be considered seriously in future studies.