The sun is seen as it sets between Manhattan buildings on 42nd Street during a phenomenon known as "Manhattanhenge," Wednesday, July 13, 2011 in New York City. (Julio Cortez/AP)

The name “Manhattanhenge” was coined by Neil deGrasse Tyson, a respected astrophysicist at the American Museum of Natural History. Tyson found this sun alignment on New York’s streets similar to the dramatic sun alignment that occurs at Stonehenge, England on the summer and winter solstices.

On May 30 – about five minutes before sunset at 8:20 p.m. – observers looking down any westward-facing street in Manhattan have the chance to catch a dramatic glimpse of the setting sun.

The big wild card for eager photographers is whether lingering clouds and shower chances will dampen the sun’s dazzling show. If that happens, tomorrow (May 31) will still offer a golden, but less perfectly aligned, sunset in Manhattan. The next opportunity for the setting sun’s alignment with Manhattan’s westward facing streets will occur on July 12, a few minutes before 8:27 p.m.

Why are May 30 and July 12 unique to New York City? On these two dates, the sun sets far enough to the northwest (300º from due north to be exact) to line up with the city’s street grid. A map of downtown Manhattan illustrates that east-west streets are actually tilted on a northwest-to-southeast angle. Moreover, New York’s low elevation allows observers to see the setting sun very low in the sky as it descends over the Hudson River.

Optimal sun orientations in other locations

If you don’t live in New York, other areas experience a similar sunrise and/or sunset phenomenon, albeit on different dates.

A similar glowing phenomenon occurs at California’s Yosemite National Park in February: on two days each year, the southwest-facing Horsetail Fall is so exactly aligned with the setting sun that the sun’s light gives the cascading water a lava-like appearance.

In Washington, D.C. the due east-west orientation of the National Mall and major cross streets allows residents to see the rising and setting sun coincide with the spring and autumn equinoxes.

In his blog post “Ducks at Sunrise”, Ambrose writes: During the spring and autumnal equinox, the sunrise aligns in the eastern sky with D.C.’s monuments and the Reflecting Pool. Within a week or so on either side of the equinox is the optimal time for photographing a Washington sunrise.

Additional reading:

Manhattanhenge proves the sun orbits New York (Bloomberg Businessweek)

Manhattanhenge: the sun, the city and a special rendezvous (NPR)

Every February, Yosemite waterfall turns to lava (Yahoo News)

(Kevin Ambrose and Jason Samenow contributed to this post)