The environmental impact of a tossed cigarette butt.
Denmark supplies three out of four of the world's offshore wind turbines, and it's on track to be free of fossil fuels by 2050.
Slideshows
Photographer Alexey Kljatov uses a reverse-lens macro technique to capture snowflakes on his balcony in Moscow.
Ask Mr. Green
Sierra sat down with Jules Howard, author of new book Sex on Earth, for a totally serious conversation about animal sex.
Three food experts create a holiday feast that will appeal to all eaters.
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Reef-building corals have found new refuge in Hurricane Hole.
Landscape Image
Just say no to receipts in fast food restaurants--especially if you've used a hand sanitizer--to avoid absorbing or ingesting high amounts of the endocrine-system-disrupting chemical BPA.
"There's a growing hunger in my generation for something raw and true."
