The Glimmer Hunt

Every light on this map so far was built to stay on. This one is built to be turned off.

For one night a year, two columns of light stand where the towers stood. Eighty-eight xenon spotlights, forty-four to a column, seven thousand watts each, six blocks south of the World Trade Center on top of the Battery Parking Garage. On a clear night you can see them from sixty miles away.

They are on from dusk to dawn. Except they are not. Through the night the keepers darken them for twenty-minute stretches.

Not because something broke. Because the light works too well on the wrong thing.

Migrating birds navigate partly by the sky. A beam that bright pulls them off course and holds them circling. A study in 2017 found the installation changed several behaviors of nocturnally migrating birds, and that the effects disappeared the moment the lights went out. More than a million birds have been caught in those beams. So the Municipal Art Society works with the NYC Bird Alliance, and when the beams are full of birds, they are switched off. Twenty minutes. Then on again.

I have been collecting lights by who they are a hand for now. This is the first one that is a hand held out and a hand that grabs at the same time, and the way it stays honest is by knowing when to stop.

It was nearly called Towers of Light. The families of the dead said no, that names the buildings instead of the people. So it carries the tribute's name, and it still draws two towers in the sky.

It was also supposed to end. It ran five weeks in 2002, then one night a year. It was announced that 2008 would be the last, and then it wasn't. Twenty-four years on it is still not permanent. Every other light on my map wants to stay. This one refuses to become furniture.

The Kugelbake stands in Cuxhaven with two discs on its tip where its lamp used to be, kept long after it stopped steering anyone. This one is the opposite. It could be kept forever and it is not allowed to be, because keeping it would cost something that is not ours.

A light that owes nothing back is the safest kind of hand. This one asks something: put me out for twenty minutes, as often as it takes, so the thing I catch can leave.

The lights come back on and go out for another year. Above the harbor, the birds that were circling are gone.