 He was later put in charge of the Central Meteorological Agency during the Meiji period, became the first person to photograph the corona of the sun in Japan, during a solar eclipse in 1887, introduced the meter system, founded Hokkaido University, and established standard time.Later in life, together with his old colleague Ōtori Keisuke, he contributed to the magazine "Kyū Bakufu", writing articles about his experiences in the 1860s, as well as about the navy of the former Shogunate.Arai died of diabetes in 1909, at the age of 74.