The Tribute in Light, which features 88 separate beams of light shooting from the WTC into the sky, has become perhaps the most beloved and evocative of 9/11 memorials. If the sky around the city is clear of clouds, the annual Tribute will be able to be seen from at least 60 miles away. You can still catch the Tribute until sunrise tomorrow, but keep in mind that the project takes weeks of preparation and hundreds of thousands of dollars to construct—so if you want to keep seeing the memorial every year, you may want to consider helping out.