After a year marked by a wave of popular uprisings, deadly natural disasters and continued economic uncertainty, millions around the world are set to ring in 2012 with a party.

The fun, and the new year, starts first in western Pacific - with 2012 beginning for residents of Samoa, Tokelau and the Christmas Islands at 5 a.m. ET.

From there, the midnight revelry will work its way west. That means fireworks over Sydney Harbor, Moscow, London and places in between.

North and South America will be the last continents to usher in 2012, with small parties and massive celebrations. Many will raise a toast to the new year, with a distinctive "drop" at midnight - from an oversized guitar in the country music capital of Nashville, Tennessee, to a drag queen in Key West, Florida.

One of the most watched such events will be in New York City, where organizers estimate hundreds of thousands will pack Times Square while more than 1 billion people tune in on television.

Lady Gaga, Justin Bieber and Drake will be among those performing ahead of the 105th annual drop of the New Year's Eve Ball, which weighs in at 11,875 pounds and contains 2,688 Waterford Crystal triangles.