That’s exactly what happens at Indian Echo Caverns in Hummelstown, Pennsylvania – a subterranean wonderland that somehow remains one of the state’s best-kept secrets despite being, well, absolutely ...

Strange cone-shaped rocks led scientists to the hidden remains of one of Earth’s oldest asteroid impacts. It could help us find fossil life on Mars.

Is Earth's inner core solid or liquid? While the inner core is extremely hot, experts have known that it is solid for many ...