It's back! Manhattanhenge, a natural phenomenon in which the sun lines up with the New York City borough's street grid when it sets for the evening, returned on Monday to the delight of residents and tourists alike. Both locals and out-of-towners gather in droves on pavements and pedestrian crossings to take photos of the moment the sun filters through the many skyscrapers, perfectly aligning with the street. Manhattanhenge takes its name from Stonehenge, the historical site in the UK where the sun rises and sets perfectly in between the stones during the winter and summer solstices. New Yorker and well-known astrophysicist Neil deGrasse Tyson created the phrase in 1997. “So, Manhattanhenge may just be a unique urban phenomenon in the world, if not the universe,” he <a href="https://www.amnh.org/research/hayden-planetarium/manhattanhenge" target="_blank">wrote in an article</a> that year. The phenomenon is visible from the east side of the Manhattan borough, looking westward. It is also visible at sunrise if people are looking eastward. After Monday, it will happen again on Tuesday, though the sun will not be perfectly aligned. This is the last time the phenomenon will come to the city borough this year until it returns next spring. It often occurs twice in the spring and twice in the summer.