PS COLUMN　ARCHIVE

April 29, 2009

The first telescope in Japan

UNESCO (UN Educational, Scientific and Cultural Organization) and IAU (International Astronomical Union) designated 2009 as “International Year of Astronomy” on the ground that this is the 400th anniversary since Galileo Galilei observed night sky by astronomical telescope for the first time in the world. There are held various memorial events in Japan to draw attention from general public to make them interested in astronomy.

It was 1609 when Galileo made a telescope single-handedly upon having heard a rumor that it was invented in Netherlands. Telescope prevailed in every part of Europe in less than no time, but when was it introduced to Japan for the first time? Japan was sealed off to the outside world around that time, so it was under difficult circumstances for Western civilization brought into the country. It is a well-known historical fact that only the route of introducing their civilization was through Dutch emissary at Dejima in Nagasaki prefecture, for it was the only open window to the outside world.

In truth, however, it was from an English gentleman that the telescope was brought to Japan for the first time as a gift. East India Company of England obtained information that William Adams (Anjin Miura by Japanese name) who had been drifted to Japanese shore some years earlier was being preferentially treated by the then Shogun Ieyasu Tokugawa, thought it would be the best opportunity for them to commence trading with Japan, and so sent a delegate by the name of John Saris to Japan in 1613. Saris was permitted, as expected, to meet Ieyasu Tokugawa by helpful efforts of Adams and handed over a personal letter from King James I. One of his gifts to the Shogun was a telescope. According to the historical materials regarding diplomacy of early Edo Period, it is described as 1.8 meters in length capable of sighting about 24 kilometers away.

From this historical data, it is known that the telescope came to Japan for the first time in 1613, which is only four years after Galileo used the telescope. I was surprised to know that the telescope had been introduced to Japan much earlier than I thought. The year 1613 is seven years earlier than the Mayflower’s arriving in America, which means the telescope came to Japan considerably earlier than to America, and that the first Japanese who got surprised by looking through a cylindrical tool is presumed, interestingly enough, to be Shogun Ieyasu. In those days Ieyasu was staying at Sunpu Castle in Shizuoka prefecture at the present time, so I imagine he might have looked down over the town by the telescope from castle tower. What Ieyasu is different from Galileo though, is that he didn’t leave evidence that he looked up at the night sky to observe moon and stars.

It is the latter half of 18th century, 150 years after the telescope was brought to Japan, when they first began looking up at night sky through telescope. There are still remained graphical charts, which described the Moon, Jupiter (including satellites) and Saturn’s rings that were observed by the telescope made by a man called Zenbei Iwahashi. I wonder why it is for the world most moon loving Japanese to have directed the telescope toward night sky only so later in years. Pioneering into the new world by a newly invented device required a genius like Galileo: does this explain the reason?

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