Fritz Koenig's Sphere for Plaza Fountain (1971).

New York Mayor Michael Bloomberg presided over the rededication Monday of a 45,000-pound sculpture called "The Sphere" in Manhattan's Battery Park.

"The sphere that rests behind me in many ways symbolizes New York," Bloomberg said of Fritz Koenig's steel-and-bronze sculpture that once stood in the fountain of the trade center plaza. (CNN)

Six months after the fatal day, New York has switched on a temporary memorial. Two rays of light were be lit from dusk until 11pm every day for the folling 32 days. A truly magnificent sight equal only to twins themselves.