October 15 is the day that the spotlight on the tip of stone b declares that the following year is a leap year.
A number of measuring stone implements were recovered from Iwaya-Iwakage in about 1968. The research team first had a look at them in February 2013. In February 2015, the functions of two of the tools were realized by Kobayashi and Tokuda.
The tool shown in the photo above was thought to be a measuring template for the leap-year spotlight of October 15 every four years.
Finally, the team could actually observe and record the event. The solar spotlight perfectly illuminated the tool on October 15 at 9:29 a.m. It was an exciting historical moment for all of us present!
Did you know that 2015 is a leap-year observation year?
At Kanayama Megaliths, leap-year observations are made in the month of October. In a normal year, a spotlight strikes the leap-year measuring stone (stone b in the above poster) for a few days up to and including October 14. For an upcoming leap year, the spotlight can be observed even on October 15. 2015 is such a year for the October 15 observation.
October 13, 2015
We were anxious to see the spotlight on the leap-year measuring stone this October. We were concerned when we had a sequence of rainy days. Finally, when October 13 turned out to be a fairly sunny day, we ventured into Iwaya-Iwakage to look. Here is what we saw.
The sunbeam has entered the chamber. The spotlight on the measuring stone does not strike the tip of the stone. The spotlight is rather diffuse due to the hazy sunlight.
October 14, 2015
We returned the following day to observe the movement of the spotlight. The day dawned crisp and clear. The spotlight was also crisp and clear, but it did not reach the tip that day. The view through the “window” shows the head of the megalith which shapes the spotlight. We end this day’s post with a shot of Yoshiki Kobayashi and spotlight.
Iwaya Rockbat’s news item: On June 28, 2015 in Gifu, Japan, an article about Kanayama Megaliths and investigator Ms Shiho Tokuda appeared in the Gifu Shimbun newspaper, in a series on Women of Gifu. The article was entitled, “Approaching the Mystery of the Spotlight” and was written by reporter Koichiro Noguchi.
“Kanayama Megaliths reveal fact, truth and essence about ancient Jomon people and their relationship with the sun,” said Ms Tokuda. She has been investigating at Kanayama Megaliths since 1998. Research still continues. In February 2015, the researchers determined a 128-year cycle of the solar calendar, which makes the Kanayama calendar one of the most accurate in the world.
Ms Tokuda’s message is that Kanayama Megaliths is a place where modern people can realize that “true human happiness is based on harmonious relationships.”