SAKIGAKE, also known by its technical designation MS-T5, was Japan's first interplanetary spacecraft. It was part of Japan's contributions to the international effort to study Halley's Comet in 1986. SAKIGAKE was equipped with instruments to measure the properties of the solar wind and interplanetary magnetic field.

AKIGAKE followed a heliocentric orbit, which allowed it to approach Halley's Comet. The spacecraft's closest approach to Halley's Comet was approximately 7 million kilometers on March 11, 1986. Although it did not carry imaging instruments, SAKIGAKE's data on the solar wind and magnetic field interactions with the comet were valuable to the overall scientific understanding of these phenomena.