New Yorkers Crack a Smile at 'Manhattanhenge'

Manhattanhenge on July 11 at 8:24 p.m. CREDIT: Henry Sene Yee | Instragram user ID: hsyee View full size image

Thousands of New Yorkers hit the streets Wednesday and Thursday at dusk to see the setting sun turn the Manhattan skyline into a Stonehenge-like sundial.

The event, dubbed "Manhattanhenge," happens on two sets of two consecutive days each summer when the sun hits the horizon exactly in line with New York City's rectangular grid, lighting up both the north and south sides of the city's cross streets. On Wednesday (July 11), the full orb could be seen perched at the horizon, whereas on Thursday (July 12), the true "Manhattanhenge," the sun tucked itself into bed perfectly in line with the streets.

Spectators snapped spectacular photos of Wednesday's show, and Twitter was atwitter with mentions of the celestial alignment. The sky didn't cooperate quite as well on Thursday, however; the sun was "trying very hard to peak through the clouds," said Twitter user Andrew Dallos. [Gallery of the Craziest Clouds]

What makes this sunset so special? Any city crossed by a street grid that heeds the cardinal directions will experience days when the setting sun aligns with its east-to-west streets, but New York has the added requirements of impressive skyscrapers and, beyond them, a clear westward view to the horizon, across the Hudson River to New Jersey.

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."

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