LOWER MANHATTAN, New York City (WABC) -- The Tribute in Light, with its beams of light shining into the night sky, is honoring those who were killed on September 11, 2001.
Although a very foggy night, the Light is still visible emerging from the site of the World Trade Center.
Assembled on the roof of the Battery Parking Garage south of the 9/11 Memorial, the twin beams reach up to four miles into the sky and are comprised of 88 7,000-watt xenon lightbulbs positioned into two 48-foot squares, echoing the shape and orientation of the Twin Towers.
"One of the first installations relied on automated light fixtures and the kind of things you might see at a rock and roll concert, just a bigger version," lighting designer Michael Hemmenway said. "And that ended up being the wrong answer because we couldn't get the type of precision control necessary to create what you see behind you."
It was initially located adjacent to Ground Zero, but designers soon realized that in order to get the best results, they'd have to move it -- and engineers and stagehands would need to tinker with it manually.
RELATED | Bill Ritter reflects on the anniversary of 9/11: A divided U.S. needs healing, unity
"So we designed a custom installation and mounting enclosure that literally relies on the threads of a screw to tilt the lights from side to side," Hemmenway said.
On a clear night, the installation can also be viewed from a 60-mile radius around Lower Manhattan.
The lights, which are best viewed when it is completely dark, were turned on at sunset on September 11 and will fade away at dawn on September 12.
9/11 21 Years Later: Click for reflections, photos and stories
* Get Eyewitness News Delivered
* Download the abc7NY app for breaking news alerts
Submit a tip or story idea to Eyewitness News