The sun sets above New York City's 42nd Street on Wednesday in a spectacular phenomenon that can be seen just twice a year. Dubbed "Manhattanhenge," it occurs when the sun aligns perfectly with the east-west streets of the main grid in Manhattan. The term alludes to Stonehenge, where the sun lines up with the stones during the solstices. Astrophysicist Neil deGrasse Tyson coined the term in 2002.