Yohkoh is a Japan/US/UK mission aiming for the study of high-energy
solar physics. Its scientific operations were conducted since early
September-1991 until 14-December-2001, while its orbital life was from
31-August-1991 to 12-September-2005.
Yohkoh was named after the Japanese word meaning 'sunshine'.
For more information about Yohkoh mission, spacecraft, and instruments, we have several versions of documents, including some external links. Hope you find the article that best meets your needs.