What planet is often referred to as the "Red Planet"?

Mars is commonly referred to as the "Red Planet" due to its distinctive reddish appearance, which is primarily the result of iron oxide, or rust, on its surface. This iron oxide reflects sunlight in such a way that it gives Mars its characteristic color, making it easily distinguishable from other planets in the night sky.

The labeling of Mars as the "Red Planet" has cultural and historical significance as well, as it has been observed and documented by various civilizations throughout history. Its color has led to associations with war and aggression, as seen in the mythological connections to the Roman god of war, Mars.

Understanding this aspect of Mars helps in grasping not just its visual characteristics, but also its place in human observation and cultural references regarding the solar system.