Year: Four Times a Year
The Manhattan grid pattern produces an effect known as “Manhattanhenge” (like Stonehenge) as, on four days of the year near the solstices --- around May 28th and around July 12th for sunset --- when the sun is directly aligned with the street grid pattern. This means the sun can be seen setting exactly over the centerline of every Manhattan street. A similar effect occurs during sunrise on December 5th and January 8th. It is also called "Manhattan Solstice." The effect was first noticed and the term coined by astrophysicist Neil DeGrasse Tyson in 2002.