The color most commonly associated with the planet Mars is red. This reddish hue comes from iron oxide, commonly known as rust, which is prevalent on Mars's surface. The presence of iron and its oxidation creates the planet's distinctive appearance, making it visible in the night sky. Mars has been called the "Red Planet" for centuries, and its color has fueled human fascination and exploration. This characteristic color contributes to the symbolism of Mars in various cultures, often associated with war and aggression due to its fierce appearance and historical associations with the Roman god of war.