Discovery has announced the lineup that will mark the launch of its latest channel Planet Green, set to debut June 4. Complete with HD simulcast, 50 million homes will greet the launch (it replaces Discovery Home Channel) of more than 250 hours of original green lifestyle programming. Look forward to programs starring Adrian Grenier of Entourage, Bill Nye the Science Guy, and others. A sneak peek will be available on VOD April 17 for those who just can't wait to enhance their environmentally-focused lifestyle.