I could be persuaded Instagram may have some value:
Even a bigger hit the second day in July (it also occurs two days in May).
But can this be accurate?
As the astrophysicist Neil deGrasse Tyson put it on the Hayden Planetarium website, “Manhattanhenge may just be a unique urban phenomenon in the world, if not the universe.”
Surely there is a phenomenon almost as cool, somewhere in the American Midwest or Mountain West, perhaps, where the good Presbyterian, Lutheran and Mormon pioneers laid out their cities and entire states with clean Cartesian grids . . . anyone got information to correct Dr. Tyson?
Maybe the question to ask, perhaps from Tyson, is how to calculate when an east-west street in your town might get a “henge” moment.
For example, how about a special sunrise at Delicate Arch, in Arches National Park? Or at Newgrange, Ireland?

Sunrise at Delicate Arch, Arches National Park, by Alex Savage

December 20, 2009, solstice sunrise at Newgrange, Ireland – Photograph by Cyril Byrne – courtesy of The Irish Times (Astronomy Picture of the Day, NASA)
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