This year marks the 55th anniversary of Earth Day! Every year on April 22, people worldwide mobilize to address some of the most urgent threats facing our environment, from climate change to ...

Ah, Earth. We may not think about our planet on a day-to-day basis, but the world we live in is a pretty interesting place. The third rock from the Sun—and to this day, the only one with known ...

Earth Day is one of the most popular and widespread non-religious holidays in the world, recognized in over 100 nations across continents. Although the event was primarily based in the United States, ...

A college student in a gas mask "smells" a magnolia blossom during the first Earth Day on April 22, 1970 in New York City. Credit - AP More than 8 billion people inhabit Earth, and soon a springtime ...

Earth Day is one of the most popular and widespread nonreligious holidays in the world. Although the event was primarily based in the United States, by 2009 the coordinators for Earth Day helped gain ...

Whales are a group of mammals that live in oceans. They include some of the largest animals on Earth. The blue whale is the biggest animal that has ever existed. Whales can be found in every ocean, ...

Where they lived: Dinosaur fossils have been found on every continent, including Antarctica. What they ate: Some ate plants, while others ate animals, including other dinosaurs. How big they were: The ...