Lights go out across planet for Earth Hour

Lights were going out across the world on Saturday as millions of homes and businesses in major cities went dark for one hour in a symbolic gesture to highlight concerns over climate change.In Australia, floodlights of the Sydney Opera House were extinguished as the city's iconic harbor kicked off events for Earth Hour, a day-long energy-saving marathon stretching through 88 countries and 24 time zones.The event's Web site reported that hundreds of people lined the harbour for a glimpse of the dimming skyline at 8:30 pm -- the local time that nearly 4,000 participating cities around the world were expected to switch off non-essential lights.Sydney became the birthplace of the Earth Hour campaign in 2007 when 2.2 million turned off their lights, igniting a grass roots movement that has become a global phenomenon.