[Aizumine March 2025 issue] Ina, Iide, Iizuna and 2

World Heritage Sites and the Sea, Mountains, Rivers, and People, Part 2

The Ina Laboratory (Director Miyahara) received a question: “Why are Mt. Iide and Mt. Iizuna named after the stars in the night sky?” I would like to explain.
The latitude and longitude of Mt. Iide (summit) is 37 degrees 51 minutes 17 seconds north and 139 degrees 4 minutes 26 seconds east, while those of Mt. Iizuna are 35 degrees 44 minutes 22 seconds north and 138 degrees 16 minutes 11 seconds east. Those of Mt. Tsukuba (Iina) are 35 degrees 13 minutes 31 seconds north and 140 degrees 16 minutes 24 seconds east. Using the “Distance and Azimuth Calculation” method provided by the Geospatial Information Authority of Japan, the distance between Iide and Iizuna is 186,510 meters, between Iizuna and Tsukuba (Iina) is 185,782 meters, and between Tsukuba (Iina) and Iide is 184,326 meters. The average distance between these three points is 185,539 meters, but since the nautical mile is 1,852 meters, an equilateral triangle of almost 100 nautical miles is derived. Strictly speaking, the Iide-Tsukuba (Iina) line is about 2 kilometers shorter than the Iide-Iizuna line. It is difficult to depict the 2/100 difference unless you draw a large triangle on a newspaper-sized piece of paper, but it is possible to depict this in the night sky. However, this is only possible in the summer night sky. This is not the “Summer Triangle” drawn by the three first-magnitude stars of Weaver Princess (alpha Begonia), Deneb (alpha Cygnus), and Hikoboshi (alpha Aquila). It is probably something that should be called the summer Great Triangle, which is unique to Japan. If you connect the stars of Polar Star, Hikoboshi (Altair, Arabic), and Arcturus (Greek), a precise equilateral triangle will emerge (Summer Stars in Tokyo, provided by the National Astronomical Observatory; triangular shape by author), projecting a line that rises firmly to the right.
Considering that each of these three mountains is named after the word “meal,” it can only be said that the naming was done with the full knowledge that the three mountains are connected. Of course, it goes without saying that our awareness of the positions of the stars in the night sky precedes that of the mountains on land. It can be said to be a projection of the night sky onto the ground.
It’s not the Kaguyahime Star, but I found this out when I was looking for the meaning of “Tsukuba” (Ibaraki) and “Tsukushi” (Fukuoka). If you think of “Tsuku-ha” and “Tsukushi,” you can understand that they are words that express the movement of the “moon” rising in the east and the “moon” descending in the west. They are then replaced with place names. “Ha” and “Shi” are antonyms, and the same goes for “Hashi” in “Hashihaka.” If you think of “Chikuma” in “Chikuma River,” it also means “Chikuma” (Nagano), and it is possible to surmise that it was originally “Tsuku-ma.” It is a river that truly reflects the moon floating in the sky and shining brighter. There is a “ma” between “ha” and “shi.” I would like to say that both “ii” and “tsuku” are “Jomon words.” Of course, “ha,” “shi,” and “ma” may all be one-syllable words with meaning that are Jomon words or ancient astronomical words.