In New York City’s New Year’s Eve celebration, aluminum replaced the original iron-and-wood ball in 1955.
The first Times Square ball, lowered in 1907, was made of iron and wood and illuminated by one hundred light bulbs. A new aluminum ball was introduced in 1920, and another aluminum version was used beginning in 1955.
The 1955 ball was lighter than earlier designs and remained in use for decades. The ball-drop tradition itself originated as a way to mark midnight at One Times Square, following the New York Times’s move there and the first celebration in 1907.
Later versions changed the appearance and technology dramatically. A crystal-covered ball was introduced in 1999 for the millennium celebration, and subsequent balls used computer-controlled LED lighting. The materials and lighting have evolved, but the descending sphere remains the ceremony’s defining symbol.