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| "The red planet. Look out for little green men! Or are they red? There's a lot of evidence that Mars once had life. But with proof like fossilized Martian micro-organisms and even structures on the surface, maybe there still is life way out there..."
Mars is the fourth planet from the Sun ( approximately 227,940,000 km or 1.52 AU away from the sun) and is commonly referred to as the Red Planet. The rocks, soil and sky have a red or pink hue. The distinct red color was observed by stargazers throughout history. It was given its name by the Romans in honor of their god of war. Mars' orbit is significantly elliptical. One result of this is a temperature variation of about 30 C at the subsolar point between aphelion and perihelion. This has a major influence on Marsą climate. While the average temperature on Mars is about 218 K (-55 C, -67 F), Martian surface temperatures range widely from as little as 140 K (-133 C, -207 F) at the winter pole to almost 300 K (27 C, 80 F) on the dayside during summer. Although Mars is smaller and colder than Earth, it is still quite similar to our planet. It has a thin atmosphere and polar ice caps, and dry riverbeds crisscross its surface (this will be elaborated further later in the page). And frozen or even liquid water may exist beneath the red Martian soil -- perhaps providing a home for living organisms. But it is not the planet described in science-fiction books and movies. There are no signs of civilizations on its surface -- past or present. |