Gyoukou (Japanese: 暁光, Hepburn: gyōkō, dawn light) is a supercomputer developed by ExaScaler [ja] and PEZY Computing, based around ExaScaler's ZettaScaler immersion cooling system.

It was deployed at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Yokohama Institute for Earth Sciences, the same floor where the Earth Simulator is located.

Amid the scandal regarding the development grant, it was removed from JAMSTEC in April 2018.

[1][2] Gyoukou is based on ExaScaler's ZettaScaler-2.x technology which features liquid immersion cooling system using Fluorinert.

A Brick consists of a backplane board, 32 PEZY-SC2 modules, 4 Intel Xeon D host processors, and 4 InfiniBand EDR cards.