Wednesday, June 20, 2012

Summer Solstice at Miantonomi's Cave

This evening I returned to the site I dubbed "Miantonomi's Cave".   It is amazing how different the site looks after three months, with all the surrounding trees leafed out.
The foliage was blocking the sunset, but I watched  the light change in this structure anyway.
Undoubtedly, the landscape was quite different in Miantonomi's time, with trees cleared away for farming.  The hill on the other side of the lake has an interesting wall and propped boulder, so there may have been a village there, with no trees obscuring the sunset.  Also, this lake is dammed, so it would have been much lower.
The cave interior was dark by 8 PM.   However, light was visible on the surface of the wall directly behind the boulder on top of the structure until sunset.  At 8:13,  this  light was visible in the small cleft upward and to the right of the broom.  Of course, this light is more diffuse than direct sunlight due to the surrounding foliage. The cave entrance is to the right.  (The broom was handy for sweeping away leaf litter.)
7:37 PM.  I was hoping for something dramatic, like a sun dagger, but what I saw was simply a triangle of light formed by the slanting side of the boulder on top of the structure.
7:49
8:12
8:21, sunset.

     Here's the diagram I used  on March 28. The bearing of the flat slanted edge of the boulder(red) is 318 degrees, so the triangle of light extends furthest to the right on summer solstice. There seem to be some slanting lines on the surface of the wall that the triangle of light fills up.  This is more obvious at 7:37 and 7:49. There also seems to be a prominent vertical mark on the wall, to the left in the photos.  It will be interesting to see how this structure looks at equinox and winter solstice.
     The changing light did reveal three strange dimples on the cave wall, below the projecting stone, which is barely visible. This was taken at 7:58.  Whether natural feature, symbol, or incidental product of Indian stonework,  these were plainly visible and quite striking.
  

1 comment:

  1. Tumamoc sum­mer sol­stice stone: http://tumamocsketchbook.com/wp-content/uploads/2012/07/mirocha_20120627_petrogluphs_P1010737.jpg

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