NEW YORK (CNN) -- New York celebrates the centennial of its most famous New Year's tradition Monday, as organizers of the Times Square ball drop have given the crystal globe an environmental makeover.

Technicians prepare the New York Times Square ball Thursday for the event's 100th anniversary.

This year the 1,415-pound ball has been outfitted with more than 9,500 energy-efficient light-emitting diodes that will illuminate the ball's more than 600 crystals. The LEDs will use the same amount of electricity as about 10 toasters, say event officials.

That's a dramatic overhaul from 1907's first Times Square ball, which was made from iron and wood and was covered with about 100 light bulbs.  Watch the computer-controlled ball »

New York police estimate about a million people will crowd Times Square to watch the ball drop from a flagpole atop the One Times Square building at midnight.

Another billion people worldwide are expected to watch the spectacle on video, said Tom Chiodo, a spokesman for the Times Square Alliance. Of those viewers, 100 million will be in the United States, he said.

New York Mayor Michael Bloomberg will be joined by Iraq war veteran Karolina Wierzchowska, who was also a Ground Zero guard worker and a New York Police Academy valedictorian -- to push the button for the ball drop at 11:59 p.m.

Weather forecasts indicate clear skies for the celebration, with temperatures in the 40s -- a mild departure from inclement weather gripping much of the Northeast.

In an effort to help people stay warm, New York City sanitation workers will be passing out "goody bags" from the Times Square Alliance that will include mittens and hats, said Chiodo.

The event will include musical performances from Hannah Montana, the Jonas Brothers, Kid Rock, Lenny Kravitz, Lifehouse, The Bravery, and alums from Fox TV's "American Idol," Carrie Underwood, Jordin Sparks and Blake Lewis.

Security inside Times Square will be tight and everyone should expect to have their bags searched at least three times, said New York Police Commissioner Ray Kelly on CNN's "American Morning."

In addition to a heavy police presence on the ground, Kelly said the NYPD's counterterrorism unit, radiation detectors and helicopters will also be patrolling the crowds.

Kelly said that once the Times Square attendees pass the entrance gates, they will not be able to leave.

New York's terrorist threat level remains at orange -- the nation's second highest level -- as it has since the September 11, 2001, attacks.

"We certainly haven't let our guard down," Kelly said.

As the ball drops, the new year will be greeted with a massive fireworks explosion, some 168 shots in the first five seconds alone, and a downpour of two tons of fireproof confetti. Some of the confetti includes New Year's wishes that were written by visitors to the city in nearly two dozen languages.

Over the past week, visitors from across the country wrote their messages on a Times Square "Wishing Wall."

"I want to turn the world green and the water clean," one person wrote.

"Let my husband stop snoring," another wrote, while others were more serious: "That my mom will get her kidney transplant" and "Peace in Pakistan." E-mail to a friend
1907 ball was covered with how many bulbs? who many people were expected to attend? what kind of power usage is it?
100 about a million energy-efficient light-emitting diodes
question: 1907 ball was covered with how many bulbs?, answer: 100 | question: who many people were expected to attend?, answer: about a million | question: what kind of power usage is it?, answer: energy-efficient light-emitting diodes