A Brief History of Amateur Astronomy in Japan

A Culture's Heritage with the Sky

By: Steve Renshaw and Saori Ihara

Originally written in November, 1996

[An adaptation of this article with illustrations appeared in Sky and Telescope, Sky Publishing Corporation, Cambridge, Mass.; March, 1997, pp. 104-08.]


Articles in this section of our site reflect only a few of the many astronomical "discoveries" made by Japanese amateurs in the past few decades. Certainly not everyone in Japan loves observing, and Japanese amateurs generally shun the idea that there is anything special about their efforts. However, despite light polluted skies and the increased difficulty of finding suitable observing sites, amateur astronomy in Japan is more widespread than ever. While some have speculated that there may be something special about the geography of Japan or even some mythological "difference" in Japanese skies that gives rise to astronomical activity, the story of amateur astronomy in Japan is really one of dedication, love for nature, the simple joy of discovery, and a sense of responsibility for education that has been passed from generation to generation for over 300 years.

There is no way to relate the story of every amateur astronomer in Japan. For this article, we relied heavily on accounts of historical and present day activity in our home prefecture, Kochi. While not completely representative of every prefecture, Kochi nevertheless provides an outstanding case study of the kinds of dedicated amateurs found throughout Japan.

Edo Heritage

No one is sure just when or where amateur activities began to emerge in Japan, but it is certain that by the early Edo era (1615-1864), amateurs were recording observations of celestial phenomena. Japan's virtual isolation from the rest of the world at this time ironically produced a situation conducive to astronomical work, especially observation. Many common citizens, making enough money to live fairly well and feeling relatively safe within the country's borders, used what leisure time they had to pursue educational avocations. Extant manuscripts of this era show strong interest in astronomical events and include observations of many amateurs.

A good example of this early activity is found in the diary of a young Kochi resident rediscovered in the 1980's. In 1664, while astronomers in Europe were trying to learn more about the motion and nature of comets, Matasaburou, a young boy of twelve, began to observe what would later be known as Comet C/1664 W1 (See The Tiger Tale Star). Encouraged by his teacher, Jian, he diligently observed the comet for over four months, wrote his impressions, and drew the changing shape of the comet in his diary. Despite the lack of astronomical knowledge, Matasaburou showed remarkable curiosity about the true nature of the "houki boshi" (brush star) and an abundant skepticism of the prevailing view among townspeople that the comet signaled doom. While his drawings do not have the flamboyance of those of Hevelius and others observing the comet in Europe, his diary shows every attempt to precisely plot the location and shape of the comet as it crossed the celestial sphere nightly. Matasaburou passed on to his own pupils the joy of discovery, and it is no doubt due to this that copies of his diary have survived the centuries.

The closest thing to a professional astronomer in the Edo era was the "calendar scholar". Such individuals concentrated on trying to keep the somewhat antiquated lunar calendar in step and alerting the emperor or local feudal governor of events portended by the "heavens" (See The Lunar Calendar in Japan). They also possessed a love and curiosity about nature that stemmed from Shinto roots. This, coupled with a strong feeling of responsibility for future generations, led several such scholars to encourage observation in the general citizenry and especially in young people. In these early times, the distinction between amateur and professional was nebulous.

The latter part of the Edo era saw several "official" observatories throughout Japan dedicated to precise observation of the sky. Some, such as the Tsuchimikado family observatory in Kyoto based observations on ancient Chinese views of the heavens, such having been the basis for calendar study and astrological reckoning for centuries in Japan. Others, such as the Asada school in Tokyo, began to incorporate "Western" methods and views of astronomy. While not actively encouraging amateurs, the work at these observatories nevertheless inspired many lay people to observe and record their impressions of the night sky.

Meiji Reconstruction and the Frontier of Amateur Development

The Meiji Restoration (from 1865) brought significant change to Japan. This included disassembling and reconstructing the old Shogunate observatories. At this time, both professionals and amateurs shed almost all Chinese practices and tried to adopt Western astronomical views and observational techniques. Much like Comet Ikeya-Seki inspired amateurs in 1965, Comet Halley's return in 1910 further energized a new generation of professionals and amateurs to search the skies for new discoveries. While many edifices of the Edo era were abandoned or destroyed in these years, fundamental cultural values mentioned earlier remained.

Interestingly, the history of astronomy in the early 20th century seems to reflect strong cooperation between amateurs and professionals. The first modern organization dedicated to astronomy was "Nihon Tenmon Gakkai" (The Astronomical Society of Japan). Founded in 1908 and open to both amateurs and professionals, the society's main purpose was education and dissemination of information about astronomy. Active observation among amateurs was encouraged, and the Society published several journals which included both professional and amateur observations.

One of the most significant figures in the Society's history was Shigeru Kanda. Having made careful observations of Halley's Comet at the age of 16, he later graduated from Tokyo University and took a post as professional astronomer at Tokyo Observatory. Somewhat like Charles P. Olivier in the West, Kanda never forgot his amateur roots. As leader of the Society, he actively encouraged amateurs to contribute records of their activity for publication. Many areas of amateur observation were encouraged including variable stars, sunspots, meteors, nova, occultations, asteroids, and of course, comets. Kanda saw amateurs as an essential part of the data gathering aspect of the science of astronomy.

The Society itself seems never to have actively sought to exclude amateurs; it seems to have been amateurs themselves who began to move away from its ranks. Apparently, some amateurs saw the ASJ as simply an arm of Tokyo Observatory and felt restricted by what they saw as a narrow and somewhat bureaucratic agenda. Obviously, as with counterparts in other countries, many amateurs found joy in observing using their own agenda, sharing their experiences informally with other "lovers of the sky", and moving at their own pace rather than being restricted by professional research programs.

Not all activity centered around Tokyo. In 1920, a professor at Kyoto University, Issei Yamamoto, began what was called the "Tenmon Doukoukai" (simply translated as Astronomy Association). Its stated purpose was not just to do research in astronomy but to foster friendship among all lovers of astronomy. Many amateurs saw this organization as "freer" and more flexible than the ASJ. Renamed the Oriental Astronomical Association in 1932, the organization continues as an umbrella for both professional and amateur activities.

The War Years

World War II had a devastating effect on Japan, and some of the most talented amateur astronomers were sent overseas, never to return. Consequently, there was a significant reduction in astronomical activity, not only because of the war effort, but also because of a paucity of equipment, books, and writing materials. Some Japanese scholars have described this period as a modern "dark age".

Still, there are amazing accounts of men and women who tried to keep the spirit of discovery and exploration alive. In May 1942, while stationed in Singapore, Minoru Honda made observations of 10th-magnitude Comet Grigg-Skjellerup with a homemade 3-inch refractor. During city-wide air-raid blackouts, Hisako Koyama would drag her futon into the yard and hide under it, lighting her variable-star charts with a small flashlight. Masahiro Yoshihara, lost his telescope during the June 1945 bombing of Yokkaichi City. Barely escaping with his life, a shell exploded close by, singeing the edges of the observing log he had held tightly under his arm. Undaunted, within a month Yoshihara was back making meteor observations.

Elderly astronomers in Japan nowadays look back to those times and, despite the horrors of war attest that some of the darkest skies were experienced on nights when shells could be heard exploding in the distance.

A Post War Generation: Inspired Scholars and Comet Seekers

As the relative safety of the Edo era provided a base for citizens to pursue avocations, economic recovery in post-war Japan and a general feeling of safety once again provide a conducive atmosphere for amateurs. With a continued love and respect for nature, a desire to educate the next generation, a curiosity for and discipline in recording detail, and the simple joy of discovery, the amateur tradition in Japan grows. These days, there are many national and local associations and societies in Japan dedicated to amateur astronomy. These include specialized groups for young, for old, for casual observers, and for dedicated specialists in most every area of astronomical interest.

The line between professional and amateur in the area of observation continues to be somewhat nebulous. A good example of an individual skirting this line is Tsutomu Seki (See Seki's 52nd Asteroid). Few readers are unfamiliar with the "finds" of this Kochi resident, the most prominent of which may be the co-discovery of Comet C/1965f, the spectacular sun grazing comet Ikeya-Seki. Present comet hunters, including Yuuji Hyakutake of recent fame, trace their inspiration back to Seki's co-discovery. While the theoretical nature of Seki's work may be questioned, his "empirical" technique in observation is an inspiration to amateur and professional alike.

In his book, Comets are Calling Me, Seki speaks of the struggle he feels in himself. "Why do I continue to search? Why do I still climb that mountain?" he asks himself. Why indeed would a man continue to do the lonely work of observation, conduct the tedious numerical reduction of orbital elements, and find only private sources for publication of his material? For Seki, recently honored for the discovery of yet another asteroid, it seems to be a lingering legacy of the Edo era: curiosity and love of the phenomena coupled with a desire to be inspired and to inspire those who follow. Such inspiration was reflected in Hyakutake's comments to

the press after his discovery of the comet bearing his name: "Why are you concentrating on me? It is the beauty of this visitor that deserves attention".

These days, in the case of dedicated observation and pure knowledge of astronomical phenomena, amateurs often rival professionals. When one browses the science shelf of any local bookstore, the number of amateur publications, many printed at the author's own expense, is staggering. Along side professional treatises, amateur books and pamphlets may be found which include works on star lore, handbooks for celestial photography, star atlases, and numerous guides for searching the skies. While the theoretical side of astronomy and astrophysics appears to be the unique domain of professionals, the observational side of astronomy is heavily weighted with amateurs.

Any clear night in Japan (and these are indeed rare, especially in Spring and Summer) will find hundreds of amateurs in every prefecture searching the skies. Those living in country areas such as Kochi may not have to look too far to find suitable observing sites. Others, such as Yuuji Nakamura (mentioned earlier as one re-discoverer of deVico) who lives in Aichi Prefecture, may drive for hours to escape city lights, sleep briefly in their cars, and scan the skies until dawn.

In the mid-1980's, Japan began construction of a number of "astronomical learning centers", many of which have planetariums, educational facilities, and telescopes available for public use. Funded by both national and local government, these public observatories provide classes for non-professionals and make their telescopes available to deserving amateurs (groups and individuals with specific observing plans and/or proven track records in astronomical education, calculation, or observation). Such is the case with Kochi amateur Keiichiro Okamura, who often observes and teaches at the Kochi Prefectural Geisei Observatory.

In many ways, Okamura represents the best in amateur astronomy in post war Japan. Calling himself a "science kid", he has actively pursued knowledge in a number of fields throughout his life, not the least of which is astronomy. He recalls nights as a boy gazing in wonder at the sky as well as listening to stories told by his family about the old calendar scholars of ancient Tosa (modern Kochi). An avid astrophotographer, Okamura's photographs of Comet Halley were used by the Halley Association of Japan in their book covering its return. He has just finished his third book, Tosa Tenmon Sanpo (Tosa Astronomical Promenade) which is based on a series of articles he wrote for the local newspaper.

Okamura often speaks of the "Edo" legacy of active observation and refinement of what he calls "classical" (non-computer, non CCD) technique. Always the educator (his actual vocation), he obviously holds dear the legacy left by individuals of that era to search for the unique, inspire the next generation, and make difficult astronomical concepts easy to grasp for their natural wonder. As he has researched the techniques and writings of ancient astronomers in Japan, he has tried to preserve as many relics of those times as possible. He has built models of the instruments they used including planispheres, armillary spheres, sun dials, and astrolabes. He has also ground and polished mirrors for his own telescopes.

It is not his accomplishments that Okamura wishes to talk about, but rather what he sees as the driving force behind Japanese amateur astronomy: a love for the phenomena and a desire to educate and inspire the next generation to know as much about nature and the heavens as possible.

The Next Generation

Tosa Juku Junior and Senior High School sits on a mountain high above the city of Kochi. In the East wing, a climb of six flights of stairs brings one to the observatory which is home for Tosa Juku's astronomy club. While not every high school has an observatory or even an astronomy club, it is not unusual to see a dome break the skyline of many high schools in Japan.

Tosa Juku's astronomy club consists of about twenty students, ten men and ten women. Yoshitaka Okazaki, the club's sponsor, has members pursue a regular program of sunspot observation. Nighttime session are regularly scheduled, and club members also send data to Japan's equivalent of an Environmental Protection Agency. "I want them to learn to use the telescope, appreciate the beauty of the skies and their own planet, and pursue their individual interests as much as possible" Okazaki told us. Nanae Yano and Machiyo Murata, wielding the observatory's somewhat cumbersome 40 cm Schmidt Cassegranian, showed us the way they make sunspot drawings "every clear day we can observe". They told us that their love for astronomy was inspired by parents, fostered by an interest in star lore, and reinforced by the joy they felt when seeing their favorite objects through the telescope. Nanae was quick to point out that club activities were really in the realm of observation, not theoretical astronomy or astrophysics.

Following the inspiration of their teacher, one still sees the legacy inspired in Edo times, refined in the Meiji era, and exemplified by eclectic amateurs such as Keiichiro Okamura blossoming in the activities of these young amateurs. While few have aspirations of becoming professional astronomers, all seem to feel the profound sense of responsibility to pass on a legacy of curiosity, dedicated observation, and the joy of discovery.

The Future

Cultural generalizations are dangerous; they are at best patronizing and at worst simply inaccurate. To say that Japanese amateur astronomers are unique from counterparts in other areas of the world would be a gross oversimplification and would feed a myth about this culture that is all too prevalent in the media both in Japan and in the rest of the world. In meeting amateurs here, one is immediately struck by the unique individualism of each one. As in other parts of the world, some talk unceasingly about their latest eyepiece acquisition or new electronic observing aid. Others eagerly talk about the romance of the heavens and the lore passed on from their grandparents. Still others seem obsessed with the implication of observations of the latest nova on theories of stellar evolution. What does seem to unite amateurs here is the same factor that may unite amateurs everywhere, a common love for the phenomena, a deep respect for nature, and a desire to share the joy of observing, both with other amateurs and with coming generations. That this love seems to appear somewhat stronger in Japan may reflect long held traditions and cultural values.

Recently, I asked Japanese students in one of my classes at Kochi University what factors they felt were most significant in their childhood. Virtually all students, even those coming from larger cities such as Okayama and Osaka, mentioned nature as the primary "love" of their youth. Such a love reflects both the agrarian heritage of Japan as well as roots found in ancient Shinto religion. When one ventures past the cities to the mountains and rivers of Japan, one quickly finds that the unique natural setting almost always has a shrine nearby. Even places where meteorites were once thought to have lodged generally have their own "Hoshi Jinja" or star shrine. This indeed seems to be the spirit that most young Japanese inherit, a spirit which above all gives nature a center stage.

Yet there is in this, like so many aspects of Japanese culture, a sense of abject contradiction. While nature is valued highly, modern development continues to see mountains "shaved" and suitable observing sites encroached upon by cities and their Pachinko parlor illumination. Everywhere one looks, the contradiction between an almost obsessive desire to "Westernize" (and bring the consequent industrialization with its myriad forms of pollution) and a strong love for nature can be seen.

Will amateur observational astronomy survive the onslaught of industrialization? Alert Japanese amateurs began to combat increasing light pollution somewhat earlier than their Western counterparts, and certainly Japanese amateurs fight as hard as those in other parts of the world to maintain suitable observing sites. No one can say for sure, but if the amateurs we have met here in Japan give any indication, it is that there can be no doubt that the sense of responsibility for future generations together with the ever present factors of curiosity and the simple joy of discovery will continue to be passed on as they have been for hundreds of years.


Non-Interview References

Editing Committee on the History of Amateur Astronomy in Japan (1987, revised 1995) Nihon Amateur Tenmon Shi (History of Japanese Amateur Astronomy), Kouseisha Kouseikaku (publishers), Tokyo.

Editing Committee on the History of Amateur Astronomy in Japan (1994) Zoku Nihon Amateur Tenmon Shi (Continuing History of Japanese Amateur Astronomy), Kouseisha Kouseikaku (publishers), Tokyo.

O'Meara, S. J. (1992) Night Sky Brightness Over Japan. Sky and Telescope, Sky Publishing Corporation, Cambridge, Mass.; November, 1992

Teraishi, M. (exact date unknown) Katsurai Soan Hikki (Soan Katsurai's Fude Writings). Hand Written Manuscript [Matasaburou's Diary], Property of Kochi Prefectural Library.


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Steven L. Renshaw

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