In what has become one of the most moving — and visible — 9/11 memorials, two giant pillars of light near where the World Trade Center's twin towers once stood were turned on in lower Manhattan this week to mark the 14th anniversary of the Sept. 11, 2001, terrorist attacks. The Tribute in Light art installation consists of 88 searchlights that create two vertical columns of light.

In a photo taken with a fish eye lens, the two beams of light meet in the art installation "The Tribute in Light" projecting in the night sky over Manhattan on Sept. 11, 2015. (Gordon Donovan/Yahoo News) People stand and inside the art installation of The Tribute in Light on Sept. 11, 2015. (Gordon Donovan/Yahoo News) The Tribute in Light is seen from the Staten Island Ferry on Sept. 9, 2015. (Gordon Donovan/Yahoo News)
(Gordon Donovan/Yahoo News) The Tribute in Light rises above the New York City skyline from the National September 11 Memorial & Museum on Sept. 11, 2015, the 14th anniversary of the 2001 terrorist attacks. (Gordon Donovan/Yahoo News) The Tribute in Light rises above the New York skyline on Friday, Sept. 11, 2015. It was the 14th anniversary of the Sept. 11 terror attacks on Friday. (Gordon Donovan/Yahoo News)
The Tribute in Light rises above the New York skyline on Friday, Sept. 11, 2015. It was the 14th anniversary of the Sept. 11 terror attacks on Friday. (Gordon Donovan/Yahoo News) People gather in the middle of one of the The Tribute in Light light installations on Friday, Sept. 11, 2015. (Gordon Donovan/Yahoo News) In a photo taken with a fish eye lens, the two beams of light meet in the art installation "The Tribute in Light" projecting in the night sky over Manhattan on Sept. 11, 2015. (Gordon Donovan)
The Tribute in Light rises above the New York skyline on Friday, Sept. 11, 2015. It was the 14th anniversary of the Sept. 11 terror attacks on Friday. (Gordon Donovan/Yahoo News) The Tribute in Light is seen from the street beneath the Battery Park Garage on Sept. 11, 2015. (Gordon Donovan/Yahoo News) A visitor takes a photo with his smart phone of "The Tribute in Light" at the National September 11 Memorial & Museum on Friday, Sept. 11, 2015. It was the 14th anniversary of the Sept. 11 terror attacks on Friday. (Gordon Donovan/Yahoo News)
The Tribute in Light rises above the New York skyline from the National September 11 Memorial & Museum with One World Trade Center to the right on Sept. 11, 2015. (Gordon Donovan/Yahoo News) The Tribute in Light rises above the New York skyline and One World Trade Center, right, Friday, Sept. 11, 2015 (Gordon Donovan/Yahoo News) The Tribute in Light rises above the New York skyline from the National September 11 Memorial & Museum on Sept. 11, 2015. (Gordon Donovan/Yahoo News)
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