Mars- the Red Planet
After Venus, Mars is our closest neighbour. It seems very earth-like. There are ice-caps on its poles, drifting white clouds and raging dust storms in its atmosphere. Seasonally changing patterns occur on its red surface. There are large dark areas on its surface called maria (meaning 'seas'). It even has a twenty-four-hour day. Mars experiences summer and winter seasons, each of which lasts for almost six earth mkths. However, the planet's distance from the Sun causes these seasonal changes to be more extreme. It is tempting to think of Mars as an inhabited world. In 1877, the Italian astronomer, Schiaparelli, observed an intricate network of single and double lines criss-crossing the bright arps of the planet Mars. He gave them the name of canali. Canali in Italian means channels or erooves. But it was promptly translated into English as 'canals'. Slnce then, people have wondered who had ma& these canals and how. Were there living- beings on the planets? Many satellites have now been sent into orbit around Mars. Two automated laboratori,es have been landed on its surface. The entire planet has been mapped. Martian surface has craters of sizes, ranging from 5 km to 121 km in diameter, created by meteorite impact. It its has enormous volcanoes.
The largest volcano on Mars, Olympus Mons or Mount Olympus is nearly three times as high as Mount Everest. It is not active any more. The Martian surface has deep ridges and valleys. Pictures alsa show islands made where water once flowed around the existing craters, and river beds, dry for hundreds of millions of years. The surface features indicate that Mars may have had both atmospher~ and ocean in the past. Viking space probes, send by U.S.A., did find evidence that 'liquid water once flowed on the planet and the atmosphere was also more dense than what it is now. Martian soil is mostly like the Earth's soil made up mainly of silicates. However, about 16 per cent of the soil is made up of iron oxide, giving it its red colour.