Tag Archives: Simulator

60 Days Before the Summer Solstice

From Friday, April 20th to Sunday 22nd, 2018
The above photo of the whole area, showing the Iwaya-Iwakage cluster on the left and the simulator building and the Senkoku-ishi grouping on the right, was taken from Highway 86 early in the morning of April 20.  Kanayama Megaliths blog has posted a new report dated April 26, 2018.   It is about the observation of 60 days before the summer solstice in the solar calendar of the Kanayama megaliths. It is the sunlight observation that tells the beginning of summer at the April 22 milestone date of the Kanayama Six-Season calendar.
At 6: 54 in the morning, light begins to stream from the top mountain. Summer observation is mainly at Senkoku-ishi. Looking at the position where the sun rises from the megalith, we see the sun just ascending from the mountain in the east at the Higashinoyama group. Now it’s past seven, and the light begins to reach Iwaya-Iwakage which is located somewhat higher than the Senkoku-ishi.
Then light begins to penetrate into the grotto of Senkoku-ishi. Around 7 a.m., sunight starts to shine on every single megalith. Although it starts out rather chilly, when the sun comes out, we feel the air of summer already.
Today Kobayashi-san is here, and there is a television interview going on. Kobayashi-san is standing in front of the shadow on Senkoku-ishi. this shadow is cast by the megalith in the lower right photo, below, on the morning of April 22.
As the sun rises higher, the grotto is illuminated, and the triangular face is very bright. On May 21, this face will be adorned with dashes of sunlight.

Winter Solstice Sunlight at Simulator and the Split Boulder

We conclude our three-part series reporting on the Kanayama Megaliths blog about the winter solstice. In the early afternoon of the solstice, the simulator is displaying perfectly the path of the sunlight. The spot of light strikes the observation panel precisely, which glows as if lit from within.

The winter sunset is also observable near the Senkoku-ishi. There is a pair of megaliths that clearly has been naturally divided in two. First take a look at the set-up. The sun is already striking the pair.



If you stand in back of the gap at sunset, you can gaze on this striking  sight!


The reason that all these winter observations are possible in the mountainous terrain of the Kanayama Megaliths is that the megalith sites are intelligently located so as to take advantage of the astronomical geometry, i.e., the line to the winter solstice setting sun. Moreover, isn’t this a magnificent view of the place where the sun goes to rest in winter?





2016 Winter Solstice Observations.   2. Solar Calendar Simulator

Ed. Note:  In our earlier post https://iwakage.wordpress.com/2016/11/13/533/ we described the Solar Calendar Simulator at the time of the October 23, 2016 observation sixty days before the winter solstice in Iwaya-Iwakage. Here, we present the accurately simulated solar direction on winter solstice day after we returned from observing the sun from Higashinoyama.

Winter Solstice 2016.12.21   再現館 Seigenkan Simulator Building.  In the early afternoon, we rested for a while at the Solar Calendar Simulator.


3419349dThe sunbeam is now hitting the center of the target board at the lowest part of it. It is 13:08; it is still a little early for the simulation. This simulator also reproduces the light of winter solstice at Iwakage 60 days prior to the solstice.

13:26  Perfect! The sunlight shines in exactly at the orientation SW 24°33’ on the face of the board that simulates Iwaya-Iwakage. (It is azimuth 204 deg 33 min in the southwest direction, as we know from astronomical software.) The simulation is exactly right!


This device was made in modern times and corresponds accurately to the movement of sunlight. The light will hit the same place tomorrow and the day after because it is around the winter solstice when the sun’s path does not change much from day to day.

If this were a spring equinox day, you would see the light moving rapidly 1 to 2 cm per day toward the front. Do you know why? If you understand this, you can see why it can be applied to leap year observations!

The simulator hall shows the foundation of archaeological astronomy in an easy-to-understand manner. For modern astronomy, this is a blind-spot.

Next:  Part 3. Iwaya-Iwakage and Senkoku-Ishi