Manhattanhenge

 

A woman photographs the sunset during "Manhattanhenge" on July 13, 2011 in New York City. This semiannual occurrence was a half-sun Manhattanhenge, in which the setting sun aligns east-west with the street grid of the city. (Photo by Michael Loccisano/Getty Images, found here)

Manhattanhenge, or Manhattan solstice, is a semi annual occurrence during which the setting sun aligns with the east-west streets of the main street grid in the borough of Manhattan, New York City. The dates of Manhattanhenge usually fall around May 28 and July 12/13. This year it falls on May 29-30 and July 11-12. 

I guess it makes for another reason to visit New York City on that particular dates :)