[2] Born in Fukuchiyama, Kyoto in 1928, Shimomura was brought up in Manchukuo (Manchuria, China) and Osaka, Japan while his father served as an officer in the Imperial Japanese Army.

[7][8] At Nagoya, Hirata assigned Shimomura the challenging task of determining what made the crushed remains of a type of crustacean (Jp.

This assignment led Shimomura to the successful identification of the protein causing the phenomenon, and he published the preliminary findings in the Bulletin of the Chemical Society of Japan in a paper titled "Crystalline Cypridina luciferin."

Shimomura worked in the department of biology at Princeton for Professor Johnson to study the bioluminescent jellyfish Aequorea victoria, which they collected during many summers at the Friday Harbor Laboratories of the University of Washington.

Their daughter, Sachi Shimomura, is director of Undergraduate Studies for the English Department at Virginia Commonwealth University and the author of Odd Bodies and Visible Ends in Medieval Literature.