Hundreds of landmarks around the world have been going dark for an hour as part of the annual Earth Hour event to highlight climate change.

The Pacific island of Samoa was the first to switch off its lighting in a symbolic gesture. New Zealand and Australia followed, with illumination turned off on buildings such as Auckland's Sky Tower and the Sydney Opera House.

In all, around 150 countries are taking part in the event, which was launched for the first time in Sydney in 2007. Lights are switched off for an hour at 8.30 p.m. local time.

As the movement spreads across the planet, buildings such as The Burj Khalifa in Dubai, the Brandenburg Gate in Berlin, the Eiffel Tower and Louvre in Paris and Buckingham Palace in London have had their illumination turned off.

In a special twist this year, Dutch astronaut Andre Kuipers is observing the event from the International Space Station and will post photos on the Internet.

53-year-old Kuipers said earlier this month: "There is no better way to raise awareness for the future of the most beautiful planet in the universe."

The environmental group WWF says the Earth Hour has grown to be the world's largest demonstration of support for action on carbon pollution.

tj/ipj (AFP, AP)