The Grand Canyon in Arizona is one of Earth's natural wonders, carved out over millions of years by the gradual erosion power ...

They were dug out by debris sent violently aloft when an asteroid or comet struck the lunar surface 3.8 billion years ago.

This impact unleashed about 130 times the energy of the current global inventory of nuclear weapons. Read more at ...

Three months after its launch from NASA's Kennedy Space Center in Florida, the agency's Europa Clipper has another 1.6 ...