As much as 45 oceans’ worth of hydrogen may be in Earth’s core, scientists reported, suggesting most of Earth’s water was ...

An experiment to quantify the amount of the universe’s lightest element in Earth’s core suggests that the planet’s water has mostly been here since the beginning ...

In Arizona, nature is diverse and dramatic. The state's Tonto Natural Bridge State Park is home to the world's largest natural travertine bridge, where visitors can hike and explore its unparalleled ...