Dr. Shimomura succeeded after 10 months. His stay at Nagoya was extended a year, and he and Professor Hirata published a paper describing their findings.
That attracted the attention of Dr. Johnson, a disciple of Dr. Harvey’s, who in 1959 offered the young scientist a job in his laboratory.
In the 1970s, Dr. Shimomura examined aequorin, green fluorescent protein and other bioluminescent materials. In 1982, he moved to the Marine Biological Laboratory as a senior scientist. He retired in 2001.
Dr. Shimomura received the Asahi Prize, one of the most prestigious honors in Japan, in 2006.
He later noted that the Washington waters where he and his co-workers had collected so many Aequorea jellyfish — 850,000 over 19 trips from 1961 to 1988 — had become polluted, and that after 1990 the jellyfish became sparse, perhaps as a result of the Exxon Valdez oil spill off Alaska in 1989. If the disappearance had occurred 20 years earlier, he would never have learned about aequorin or green fluorescent protein.
Dr. Shimomura is survived by his wife, Akemi Shimomura; a brother, Sadamu; a sister, Setsuko; a son, Tsutomu; a daughter, Sachi Shimomura; and two grandchildren.
In 2013, Dr. Shimomura went to Los Alamos National Laboratory in New Mexico, the birthplace of the atomic bomb, to give a talk about green fluorescent protein. While there, he asked John E. Pearson, the Los Alamos scientist who had invited him, about the parachutes he had seen dropped by the first B-29 over Nagasaki. He had been told they carried instruments to measure the explosion.
After some hunting, models of the original parachute payloads were found.
“Some guy came up and started explaining what we were looking at,” Dr. Pearson recalled. “Osamu said, ‘Yes. I watched them falling.’ I don’t think I’ve ever seen anyone quite as stunned as that guy.”
