Tonight at 8:30pm is Earth Hour, and annual event where hundreds of monuments around the globe go dark for an hour in order to promote sustainable energy and conservation. This year more than 170 countries are taking part, from the Eiffel Tower, Big Ben, Times Square and even the International Space Station. Earth Hour started in Sydney Australia in 2007 and has grown each year. In order to support this tonight from 8:30pm to 9:30pm turn off all of your lights and share this link to spread the word!!