It's 9/11, a date that will never be free from the horrible memories of the terrorist attacks that killed almost three thousand people in New York, Washington DC and the fields of Pennsylvania.

Every year, the Municipal Art Society of New York commemerates the tragic events with its Tribute in Light, eighty-eight 7,000-watt xenon light bulbs aimed at the sky in a way that echoes the shape and orientation of the Twin Towers. The memorial reaches four miles high and is the strongest shaft of light ever projected from earth into the night sky.

Each year, numerous photographers gather with their tripods to capture this amazing sight.

Actually, the lights are tested briefly on the nights before 9/11, so a few of this year's photos have already been shown on the web.

The lights will be on from dusk to dawn, but will be turned off for brief periods to prevent migratory birds from becoming disoriented.

The weather forecast calls for thunderstorms early in the evening and partly cloudy skies afterward.

The Municipal Art Society publishes a list of good viewing spots. There's also a discussion on DPReview about where to go.

By John van Rosendaal

Image by Greg Chow via Creative Commons