The opening of the World Trade Center Transportation Hub’s Oculus will take a rain check on the 17th anniversary of 9/11, according to Steve Coleman, a spokesperson for the Port Authority.

Designed by Santiago Calatrava, the 335-foot-long skylight was designed to allow the “Way of Light” to pass through the main hub of the transit hall at 10:28 a.m.—the moment that the North Tower of the WTC collapsed on September 11, 2001. Symbolizing the light that continues to shine through after the darkness of the tragedy, the Oculus opening allows light to fill the massive space as a memorial to the attacks on the twin towers.

The Transportation Hub is conceived at street level as a freestanding structure situated on axis along the southern edge of the “Wedge of Light” plaza. As described in Daniel Libeskind’s master plan for the site, the Plaza is bounded by Fulton, Greenwich and Church Streets to the North, West and East respectively and Tower 3 to the south. Calatrava’s design used the angle of light as a guiding principle for orienting the transportation hub. Each year, a beam of light can pass through the opening in the roof and projects all the way down the center of the Oculus floor.

Calatrava speaks of light as a structural element in the Hub, saying that the building is supported by “columns of light.” At night, the illuminated Oculus serves as a lantern in the reconstructed WTC site. On September 11th of each year, as well as on temperate spring and summer days, the Oculus’s operable skylight opens to bring a slice of the New York sky into the building. A placard at the Oculus explains:

On 9/11 each year, weather permitting, the skylight of the Oculus will be opened to allow the sun to fill this entire space. Envisioned by Santiago Calatrava to symbolize a dove released from a child’s hand, the Oculus is situated at an angle in contrast to neighboring buildings and even the entire grid of the city, thereby allowing the light to shine directly overhead and for the sun to move across its axis exactly on September 11th each year.

Source: ArchDaily