Mars
by Devon Hope
Mars History and Naming
Mars is named after the ancient Roman god of war, as befitting the red planet's bloody color. The Romans copied the ancient Greeks, who named the fourth planet from the sun after their god of war, Ares. Other civilizations also typically gave the planet names based on its color — for example, the Egyptians named it "her Desher," meaning "the red one," while ancient Chinese astronomers dubbed it "the fire star," .
Geology
The tallest mountain and the deepest valley in the solar system belong to Mars. Olympus Mons is roughly 17 miles (27 kilometres) high, about three times as tall as Mount Everest, while the Valles Marineris system of valleys can go as deep as 6 miles (10 kilometers) and runs east-west for roughly 2,500 miles (4,000 kilometers), about one-fifth of the distance around Mars and close to the width of Australia or the distance from Philadelphia to San Diego. The Valles Marineris is named after the Mariner 9 probe that discovered it in 1971. Scientists think the Valles Marineris formed mostly by rifting of the crust as it got stretched. Individual canyons within the system are as much as 60 miles (100 kilometers) wide. They merge in the central part of the Valles Marineris in a region as much as 370 miles (600 kilometers) wide. Large channels emerging from the ends of some canyons and layered sediments within suggest the canyons might once have been filled with liquid water. Many regions of Mars are flat, low-lying plains. The lowest of the northern plains are among the flattest, smoothest places in the solar system, potentially created by water that once flowed across the Martian surface. The northern hemisphere mostly lies at a lower elevation than the southern hemisphere, suggesting the crust may be thinner in the north than in the south. This difference between the north and south might be due to a very large impact shortly after the birth of Mars.
Weather
-80°F is the average temperature for Mars, but at the poles in the winter it can vary to -195°F and at the equator during midday it can be up to 70°F. The carbon-dioxide-rich atmosphere of Mars is also roughly 100 times less dense than Earth's on average, but it is nevertheless thick enough to support weather, clouds and winds. The density of the atmosphere varies seasonally, as winter forces carbon dioxide to freeze out of the Martian air.
Living On Mars
The possibility of living on Mars is many years away from being a successful venture for people who are willing to pay to go to Mars. Currently there are 78,000 people who are willing to pay to go and train to visit Mars, but because of the temperature and weather conditions on the Red Planet it is almost impossible to live there. Gases are another problem because 95% is Carbon Dioxide, 3% Nitrogen, 1.5% Argon and it has traces of other gases including Water Vapour and Oxygen.
The Ability To Grow Food and Water
No greenhouses exist there yet, of course. But long-term explorers, on Mars, or the moon, will need to grow plants: for food, for recycling, for replenishing the air. And plants aren't going to understand that off-earth environment at all. It's not what they evolved for, and it's not what they're expecting. In recent experiments, supported by NASA's Office of Biological and Physical research, Ferl's group exposed young growing plants to pressures of one-tenth Earth normal for about twenty-four hours. In such a low-pressure environment, water is pulled out through the leaves very quickly, and so extra water is needed to replenish it. But, says Ferl, the plants were given all the water they needed. Even the relative humidity was kept at nearly 100 percent. Nevertheless, the plants' genes that sensed drought were still being activated. Apparently, says Ferl, the plants interpreted the accelerated water movement as drought stress, even though there was no drought at all.
Nasa: there could have been life on Mars
Beyond Planet Earth: Exploring Mars
Bibliography
. N.p.. Web. 23 May 2013.
<http://www.ozgate.com/infobytes/mars_atmosphere.htm>.
Darling, D.. N.p.. Web. 23 May 2013. <http://www.daviddarling.info/encyclopedia/M/Marsatmos.html>.
Coffey, J.. N.p.. Web. 23 May 2013.
<http://www.universetoday.com/14872/air-on-mars/>.