Photo/Illutration Masatsugu Minami’s notebooks include sketches of Mars he drew with a pencil. (Yasuji Nagai)

Long before probes began exploring the solar system, Masatsugu Minami was peering at the red planet through a telescope and drawing what he saw.

And he kept drawing, for more than half a century.

Now, the tens of thousands of sketches of Mars by the late amateur astronomer have been included in the collection of the noted Lowell Observatory in the United States for the benefit of researchers.

The records fill 90 notebooks kept since 1969 by Minami, who lived in Fukui Prefecture and observed the planet for nearly 65 years until he died this past January at the age of 80.

They were sent to the U.S. observatory, which is renowned for its Mars-related research, with the aim of allowing researchers to take advantage of important documents detailing Martian activity recorded before high-sensitivity imaging technology or space probes were introduced.

Minami received a Ph.D. in particle physics at Kyoto University's Faculty of Science, studying in the lab of Hideki Yukawa (1907-1981), who won the Nobel Prize in Physics in 1949. He also worked as an assistant at the university's Research Institute for Mathematical Sciences.

Although the atmosphere of Mars, which orbits just outside Earth, mainly comprises carbon dioxide, there is also vapor, causing meteorological phenomena.

For example, the surface pattern of Mars is entirely obscured by massive sandstorms that occur every several years.

Minami started actively observing the planet while he was in junior high school and kept records using not only a 20-centimeter reflecting telescope set up at his home, but also a refracting telescope on the roof of the Fukui City Museum of Natural History.

He made up to seven or eight sketches in a single night when Mars came closer to Earth every two years and two months.

The plan to donate his records for future research was presented by U.S. writer and stargazer William Sheehan, 65, who was a friend of Minami, to his widow, Tomoko, 76, and the Lowell Observatory.

“The notebooks recording Masatsugu’s lifelong passion for the red planet will now be carefully preserved and remain available to inform Mars observers, such as myself, in times to come,” said Sheehan. “I feel gratified that this monument to his extraordinary dedication and skill will exist for generations to come.”

Tomoko also welcomed the move.

“Throughout his life, my husband spoke of how important it is that researchers make continual observations in positions not compromised by the politics or economy of the time,” she said. “It will make me very happy if his achievements are re-evaluated.”

Minami served as head of the Mars division of the Oriental Astronomical Association, which comprises both professional and amateur astronomers, for 20 years since 1990. He interacted with stargazers in more than 10 countries and sent more than 480 copies of his reports on Mars written mainly in English from 1986.

“He believed accumulated records of normal conditions of the planet are as important as those showing rare phenomena that occur only once in several decades,” said Takashi Nakajima, 79, who observed the planet with Minami as a classmate at the same junior high school.

“He would explain how significant it is for astronomers to keep observing objects with their eyes even in the era of probes.”

Tomio Akutsu, a 64-year-old stargazer who was on friendly terms with Minami for more than 30 years, also admired his tireless efforts.

“He could be called the last naked-eye observer in the world,” Akutsu said. “His achievements should be more highly appreciated by future generations.”

(This article was written by Asako Hanafusa and Yasuji Nagai, a senior staff writer.)