On the 50th anniversary of Earth Day, celebrate the planet and the global holiday that spawned the modern environmental movement devoted to preserving, protecting, and celebrating earth with Beautiful Phenomena from editors of TIME. This special edition pairs stunning photographs with clear, authoritative text that explains the how, what, why and when of nature’s wonders, including eclipses, rainbows, lightning, supermoons, auroras and so much more. Learn about the scientific breakthroughs that come from observing solar eclipses and other natural phenomena over the centuries, and discover the latest theories about them that are emerging today. From space, to the oceans, or land, these natural wonders hold the keys to our understanding of the world around us. Explore their mysteries with TIME Beautiful Phenomena.