Artist impression of the four classes of planetary system architecture. A new architecture framework allows researchers to study an entire planetary system at the systems level. If the small planets ...

Shooting a lever action is often compared to driving a manual sports car; both require a unique level of engagement. Just as ...

Mechanical devices can change one form of force to another. All moving parts work on some sort of mechanism. Mechanical systems all involve an input, process and produce an output. There are three ...

Source: NOVA: "Secrets of Lost Empires: Easter Island" This resource was adapted from NOVA: "Secrets of Lost Empires: Easter Island." Archaeological evidence suggests that ancient peoples were able to ...