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What and when is Manhattanhenge?
Every year around May 29 and 30 – and again around July 12 and 13 – people in New York City look forward to Manhattanhenge. It’s a phenomenon where the sunset aligns perfectly with east-west oriented streets of Manhattan, particularly along 14th, 23rd, 34th, 42nd and 57th Streets.
Viewers can also witness the phenomenon from the Tudor City Overpass in Manhattan or Hunter’s Point South Park in Long Island City, Queens. Regardless of where you watch the sunset, make sure you’re as far east as possible while keeping New Jersey in the background across the Hudson River to accentuate the effect. If you’re in the New York City area, think photo opportunity.
The two sets of aligned sunsets are centered on the summer solstice, leading to the effect’s other, incorrect name the Manhattan Solstice. The first set of 2022’s Manhattanhenge dates are May 29 and 30 (Memorial Day weekend for Americans). You can see the top half of the solar disk at the horizon on the New York City street grid on at 8:13 p.m. EDT Sunday, May 29, 2022. You can see the full disk of the sun the next day at 8:14 p.m. EDT, Monday, May 30.
As the sun appears to move south again after the solstice, the effect repeats in reverse. The full solar disk appears at the horizon at 8:20 p.m. EDT on Tuesday, July 12, 2022. Then, the half disk alignment occurs the following day at 8:21 p.m. EDT, Wednesday, July 13.
Six months later, Reverse Manhattanhenge happens around the mornings of January 11-12, when the rising sun creates the same effect on the other side of the island at around 7 a.m. EST.
Solstice and equinox alignments around the world
The phenomenon of Manhattanhenge is fun, and one of many similar alignments that occur around the world on various dates. Think Stonehenge at the equinoxes and solstices.
The point of sunset along the horizon varies throughout the year. At this time of year – between the March equinox and June solstice – the sunset point is shifting northward each day on the horizon as seen from around the globe. It’s the northward-shifting path of the sun that gives us summer in the Northern Hemisphere and winter in the Southern Hemisphere. And it’s the shifting path of the sun that gives people various alignments of the sunset with familiar landmarks.
Where to see Manhattanhenge
You can observe Manhattanhenge from lots of different places on the east-west streets of the Manhattan street grid. The best places to watch Manhattanhenge are wide streets with an unobstructed view toward New Jersey across the Hudson River. You can also put your favorite of the city’s iconic buildings in your view.
Popular spots are 34th Street near the Empire State Building and 42nd Street near the Chrysler Building. Wide cross streets – such as 14th, 34th, 42nd and 57th Streets – that ensure the best views of the west-northwest horizon (toward New Jersey) are generally good spots.
Keep in mind – especially during these covid times – that Manhattanhenge draws large crowds, especially around the city’s landmarks.
Why does Manhattenhenge happen?
The June solstice on June 21 will bring the sun’s northernmost point in our sky and northernmost sunset. Afterward, the sun’s path in our sky, and the sunset point, will both start shifting southward again. As for the sun’s alignment with the city of New York, and the streets of Manhattan Island … well, thank the original planners of this city. Scientific American explained:
The phenomenon is based on a design for Manhattan outlined in The Commissioners’ Plan of 1811 for a rectilinear grid or gridiron of straight streets and avenues that intersect one another at right angles. This design runs from north of Houston Street in Lower Manhattan to just south of 155th Street in Upper Manhattan. Most cross streets in between were arranged in a regular right-angled grid that was tilted 29 degrees east of true north to roughly replicate the angle of the island of Manhattan.
And because of this 29-degree tilt in the grid, the magic moment of the setting sun aligning with Manhattan’s cross streets does not coincide with the June solstice but rather with specific dates in late May and early July.
Bottom line: Each year around May 29 and 30, and again around July 12 and 13, New Yorkers watch for Manhattanhenge.
Read more about Manhattanhenge from ScientificAmerican.com
The post Manhattanhenge: When to see it in 2022 first appeared on EarthSky.
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