The phenomenon known as Manhattanhenge in New York City. Photo by deshaunicus.

Native New Yorkers seem to possess a kind of devotion to their city that goes beyond the usual hometown pride (for comedic insight into the NYC mindset, check out this map of the United States as seen by a New Yorker). So events like Manhattanhenge, when heavenly bodies align to cast a mathematically perfect glow across the city, seem to confirm in a Stonehenge-esque way the spiritual importance of the place.

The reality is that Manhattanhenge occurs because of the way New York City’s 200-year-old city grid is constructed. The east-west layout of streets and avenues means that twice a year, when the sun rises at due east and sets at due west, it aligns precisely with the east-west axis of the street grid.

Of course, this means that any city in the world with a rectangular grid could experience a similar astronomical effect – but New York City is rather perfectly set up for it with the clear view to the horizon and light-reflecting skyscrapers.

The exact dates of this phenomenon will vary each year according to the summer solstice, but as a general guide, Manhattanhenge usually occurs at the end of May and again mid-July. Once you’ve got the date sorted, you’ll need to stake out the best vantage point. Here’s some advice from New York’s Hayden Planetarium:

“For best effect, position yourself as far east in Manhattan as possible. But ensure that when you look west across the avenues you can still see New Jersey. Clear cross streets include 14th, 23rd, 34th, 42nd, 57th, and several streets adjacent to them. The Empire State building and the Chrysler building render 34th street and 42nd streets especially striking vistas.”

You’ve got to hand it to New York for turning a fluke of nature into a show-stopper.