Lily wrote:http://www.haydenplanetarium.org/resources/starstruck/manhattanhenge
What will future civilizations think of Manhattan Island when they dig it up and find a carefully laid out network of streets and avenues? Surely the grid would be presumed to have astronomical significance, just as we have found for the pre-historic circle of large vertical rocks known as Stonehenge, in the Salisbury Plain of England.
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May 30th, and July 12th, the setting Sun aligns precisely with the Manhattan street grid.
hahaha, very good.
Yes, everything is an alignment that way. Something on the ground always lines up with something rising/setting/passing in the sky at some point, and you can calculate them fairly easy. The only thing is that either the date or the structure needs to be fixed. Manhattan is a fixed structure, so you come up with arbitrary dates. In Stonehenge the dates are fixed. (Unless it is a coincidence that some of the stones line up with the solstices).
I want to build my own henge someday ;-).