Twice a year, New Yorkers are dazzled by sunrises and sunsets lining up perfectly with New York City’s Manhattan grid, a phenomenon known as Manhattanhenge. That it is a man-made but unintended phenomenon makes Manhattanhenge a semi-naturally occurring wonder.
The name Manhattanhenge was popularized by Astrophysicist Neil deGrasse Tyson, referencing the famous monument’s construction lining up with the Vernal Equinox and Autumnal Equinox. Other cities dub days in which the sun aligns with its grid system as their particular “henge,” but Manhattan is uniquely positioned to have one of — if not the — most spectacular example since one can get a clear view to the horizon on streets that run east to west. The best views can be found on 14th, 23rd, 34th, 42nd, and 57th. Views are best as far east as possible, while still being able to see New Jersey.
Since Manhattan is not laid out in a perfect east-west configuration, Manhattanhenge occurs on seemingly random dates in the late May and again in mid-July. This is due to the city’s designers pitching the city’s grid 30 degrees east of due north. In contrast, Baltimore’s city grid is only 3.9 degrees off and its “henge” aligns much more closely with the equinoxes. Baltimore city surveyor Philip Jones Jr. used a magnetic compass to determine where north was without compensating for the difference between magnetic north and true north. Because magnetic north was off by 3.9 degrees in 1730 when Jones was conducting his work Baltimore, the oldest streets lie just shy of a true north-south line as found in Stonehenge.
Without written record, modern-day anthropologists have assigned meaning to the particular alignment of Stonehenge from religious significance to prehistoric science and forecasting. While one cannot ever know its true purpose, there is general consensus on the significance of its seasonal agreements. It is possible to think that future generations will find the ruins of Manhattan and assign similar import in regards to Manhattanhenge. Some have even posited that since the dates typically align with Memorial Day and All-Star Break, it may seem as though War and Baseball are the pinnacles of American culture to future anthropologists.
Manhattanhenge is also a unique time for Manhattanites to ruminate on the universe outside the big apple. The convergence of nature, astronomy and science all in the dirty urban bubble of New York City is truly a rare experience, not to be missed. This year you can catch a glimpse on July 12 and 13 at sunset.
People line the streets to catch a glimpse of Manhattanhenge’s sunset.