Crowds from across New York City gathered on the east-west thoroughfares of Manhattan on Memorial Day and on Tuesday to watch the city’s biannual Manhattanhenge spectacle.
The sun set perfectly in line with the east-west streets of the city on Tuesday, while on Monday, only half the sun was visible setting between the skyscrapers.
Pictures and videos were posted to social media from around the island, with people looking on in awe at the strange spectacle.
Photo by Alexi Rosenfeld/Getty Images
“#Manhattanhenge was totally show stopping this evening 5/30/23. Manhattanhenge is the most breathtaking phenomenon that occurs twice a year when the setting sun exactly aligns with New York City’s grid,” tweeted @VenusNabs on Tuesday.
“NYC, forever and always,” another user @lorenzo_quiogue tweeted, showing the crowds also gathered to snap a picture of the event.
This phenomenon has been dubbed Manhattanhenge by astrophysicist Neil deGrasse Tyson, referencing the alignment of the sun with the U.K.’s Stonehenge Heel Stone on the summer solstice. Unlike Stonehenge, however, Manhattanhenge was a serendipitous accident of city design.
“In the 1800s a plan was put in place to guide the development of the island and the commissioners at that time decided to create 90 degree angles with the cross streets which happen to face (in general) East-West,” Jacqueline Faherty, an astrophysicist from the American Museum of Natural History in New York, previously told Newsweek.
“When they did that they created a bullseye for the sun to hit when it sets on or around May 29 and July 11,” Faherty said.
Manhattanhenge usually occurs around three weeks before and after the summer solstice of June 21, which is when the sun’s direction best aligns with the east-west streets of the island. Some of the best spots to view the sunset include 14th Street, 23rd Street, 34th Street, 42nd Street and 57th Street.
In December and January, the city also sees a so-called reverse Manhattanhenge, where the sunrise aligns with the grid on either side of the winter solstice. The summer version is much more popular with the crowds, however.
The reason for this only occurring twice per year is due to the angle of the Earth relative to the sun.
“All of this is attributable to the fact that the Earth is tilted 23.5 degrees with respect to the orbit it takes around the sun. As such there are times when Manhattan is pointing more directly toward the sun (during summer) and times when it is less directly toward the sun (during winter.)” Faherty told Newsweek in May last year. “It is all about the angle. If you go off the grid by even a degree you will be out of alignment,”
Other cities also experience their own form of the phenomenon as the sun rises and sets in alignment with the east-west grid: Chicagohenge and Baltimorehenge occur close to the spring and autumn equinoxes in March and September, while Torontohenge occurs in February and October. The difference in dates is due to the difference in the exact direction the east-west streets face. If a city had exactly north-south and east-west facing streets, then the “henge” event would occur exactly on the spring and autumn equinoxes, around March 20 and September 23 respectively.
If you missed it, no need to fret: this year’s second Manhattanhenge will occur on 12 July at 8:20 p.m. and on 13 July at 8:21 p.m. local time, so long as the weather remains clear: in previous years, the sunset hasn’t been visible due to overcast or rainy conditions.
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