Manhattanhenge
Photo: Chang W. Lee/The New York Times
No, it’s not a new Eddie Izzard sketch, Manhattanhenge is semi-annual occurrence where sun sets exactly parallel to Manhattan’s east-west streets. The term was coined in 2002 by Neil deGrasse Tyson, an astrophysicist at the American Museum of Natural History.
Manhattanhenge sunsets usually occur on May 28 and July 12. Manhattanhenge sunrise falls approximately on December 5 and January 8. The reason there are two dates for each, is that the east-west streets of Manhattan’s grid layout are offset 28.9 degrees from true east-west; as such, the sun passes this point as it approaches and recedes from the true equinox points. The reason for the 28.9 degree tilt of the streets is that while the streets are perpendicular to the spine of Manhattan, the tall and narrow shape of Manhattan is tilted to the east by 28.9 degrees.