MARS

Mars, the fourth planet from the Sun, is often called the "Red Planet" due to its reddish appearance, caused by iron oxide (rust) on its surface. It is a terrestrial planet with a thin atmosphere primarily composed of carbon dioxide, with traces of nitrogen and argon. Mars has a diameter of about 6,779 kilometers, making it roughly half the size of Earth. The planet's surface features vast deserts, large volcanoes like Olympus Mons (the largest volcano in the solar system), and a massive canyon system known as Valles Marineris. Despite its cold and arid environment, Mars is of great interest to scientists because of its potential to have harbored liquid water in its past, with evidence of ancient river valleys, lakebeds, and minerals that form in water. Today, water on Mars is mostly locked in polar ice caps or underground, but recent missions have detected seasonal flows of briny water on its surface. Mars experiences seasons due to its axial tilt, similar to Earth, but its year lasts 687 Earth days.

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