Manhattanhenge 2019: When and Where to Watch, If It’s Not Too Stormy

New Yorkers, get ready for another chance to marvel at Manhattanhenge.

For two days every spring and summer, the sunset lines up with Manhattan’s street grid, creating a gorgeous celestial spectacle. For a brief moment, the sun’s golden rays illuminate the city’s buildings and traffic with a breathtaking glow.

“It’s the best sunset picture of the year that you will have in this beautiful city,” Jackie Faherty, an astrophysicist at the American Museum of Natural History said to The Times in a 2017 interview. “Sometimes they call it the Instagram holiday.”

Manhattanhenge’s name is a homage to Stonehenge, the monument in England believed to have been constructed by prehistoric people and used in rituals related to the sun. During the summer solstice, the sunrise there is perfectly framed by its stone slabs.

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When is Manhattanhenge?

Last year, Manhattanhenge in May was blocked by pesky clouds. But if weather permits, you can catch the dazzling display at the following days and times, according to Dr. Faherty:

• Wed., May 29, 8:12 (and 30 seconds) p.m. Eastern time

• Thurs., May 30, 8:12 p.m. Eastern time

On Wednesday, dark clouds over Manhattan in the late afternoon dimmed the prospects of a good sunset. The National Weather Service warned of hazardous heavy rain and lightning strikes across the region into the early evening.

Some 200 years ago, the architects who created the plan for modern Manhattan decided to build it using a grid system with avenues that run north and south and streets east and west. That choice inadvertently set the stage for Manhattanhenge, according to Dr. Faherty.

“They created this bull’s-eye for the sun to hit,” she said.

The sun moves slightly along the horizon throughout the year as Earth tilts along its axis. That means there are times during the year when the setting sun lines up with the east- and west-running streets in Manhattan.

If Manhattan were laid out so that it aligned exactly with east and west on a compass, Manhattanhenge would occur on the spring equinox and the fall equinox. Instead, the city is 30 degrees from cardinal east and west, so the dates are shifted.

Manhattanhenge appears either as a full-sun event or a half-sun one.

What’s the difference between a half sun and a full sun?

Manhattanhenge happens in pairs, as a full sun one day and a half sun the other. The full sun is when the bottom of the sun kisses the city grid, according to Dr. Faherty. The half sun is when the middle of the sun touches the grid.

Is the view better in May or July?

There’s no real difference between the two except the order in which the sunsets occur. This year, we get the half sun on May 29 and the full sun on May 30. This summer, we’ll get the full sun on July 12 and the half sun on July 13. So the order is half-full-full-half.

Whether you get a good show depends on how cloudy it is.

Where are the best places to watch?

The key is finding a spot with a clear view of New Jersey. Dr. Faherty suggests going to a point where the streets are wide and the buildings are beautiful.

The most popular spots are 42nd Street, with its flashing signs, as well as 57th, 34th, 23rd and 14th Streets. There you will see people bobbing in and out of the crosswalk, hoping to snap the perfect sunset. Because you have to be in the middle of the street to see Manhattanhenge, remember that safety comes first.

People also throng to the Pershing Square overpass near Grand Central Terminal, but that location is very close to traffic. The police are well aware of this and frequently disperse the crowds. A safer option is the Tudor City overpass near the United Nations, but amateur and professional photographers get there very early and leave little room for the casual sungazer.

Don’t forget the other boroughs, Dr. Faherty added. Gantry Plaza State Park in Queens also has a nice view of the spectacle.

Do other cities around the world have ‘henges’?

Manhattan isn’t the only place with a “cityhenge.” There’s also Chicagohenge, Bostonhenge, Phillyhenge, Torontothenge, and Montrealhenge, among others.

“If your streets are anywhere close to east or west, my default statement is you’re going to have a ‘henge,’” Shane Larson, an astronomer at the Adler Planetarium in Chicago, told The Times in 2016. “You just need to find out when.”

Reverse Manhattanhenge

If you’re an early riser who doesn’t mind chilly mornings, you could have a chance every winter to catch a Manhattanhenge at sunrise.

Early every December and January, the rising sun aligns again with the city streets. On a clear winter morning, it has the same dazzling effect as the spring and summer sunsets but typically draws a much smaller crowd.