A series of increasingly capable spacecraft were sent to explore the inner planets Venus and Mercury. The history of that planetary exploration is traced in thi

Stargazers have observed Mercury, Venus, and Mars—the other small, rocky planets in our solar system besides Earth—for thousands of years. More recently, we

Examines the surface, atmosphere, and characteristics of the inner planets, and discusses how they are explored and studied.

People have been studying the solar system's inner planets for years. Mercury, Venus, and Mars are Earth's closest neighbors, and scientists are still learning