By YUKI EDAMATSU/ Staff Writer

The finished bottle of the sake brewed in outer space (Provided by Dassai Inc. and Mitsubishi Heavy Industries Ltd.)

The first sake brewed in outer space has already sold out on Earth, despite the astronomical price tag.

Sake brewery Dassai Inc. and Mitsubishi Heavy Industries Ltd. said they created the beverage in a simulated lunar gravity environment aboard the International Space Station.

The sake was limited to just one bottle, which cost 110 million yen ($700,000), and was quickly bought, the companies said.

The alcoholic fermentation test on the space station was part of the Dassai Moon Project, which was born from the idea of brewing sake on the moon for future human settlements.

Brewing equipment, developed jointly by Dassai based in Yamaguchi Prefecture and Tokyo-based MHI, and raw materials were carried aboard the seventh unit of the domestically produced H-3 rocket and the HTV-X resupply vehicle to the ISS in October 2025.

Kimiya Yui, a Japanese astronaut, was in charge of the experiment.

The equipment stirred the specimen mixture and used sensors to monitor the temperature and alcohol concentration levels.

The test was carried out over about two weeks from November through December 2025 under simulated lunar gravity, which is about one-sixth of the gravity on Earth, aboard the “Kibo” Japanese experiment module on the ISS.

The “moromi” sake mash that resulted from the fermentation process was returned to Earth in March 2026.

An analysis found the beverage had a 12-percent alcohol content, showing that sake can be brewed under lunar gravity in much the same process as that on Earth.

However, the ISS fermentation proceeded more slowly than on Earth, indicating that gravitational conditions may affect the process.

About 26o grams of moromi was refined into 116 milliliters of sake, and 100 milliliters of them were sealed in a titanium bottle.

The bottle was sold for 110 million yen, including tax, to an unidentified purchaser, the companies’ officials said, adding that the proceeds will be donated to Japan’s space development efforts.

In the years to come, the companies plan to work with Tohoku University to analyze the sake lees, the residue from the refining process, to see how yeast changes in outer space.