Stars get in holiday spirit for Rockefeller Center tree lighting

The heart of Manhattan will soon be ablaze with 45,000 LED lights gracing an 85-foot-tall Christmas tree in Rockefeller Center.

On Wednesday evening, the air will reverberate with the voices of Lady Gaga, Tony Bennett, Mariah Carey, Cyndi Lauper and other music stars for the nationwide live broadcast.

Tens of thousands of people are expected to stand behind police barricades to watch the annual spectacle.

Since the Great Depression, the Rockefeller Center tree has represented Christmas in New York City.

The lighting ceremony will be broadcast live on NBC starting at 8 p.m. ET.

This year's tree, a Norway spruce weighing 13 tons, is from central Pennsylvania and will be on display through Jan. 7.