We all know that Mars is the fourth planet of the Solar System. The dawn temperature was around — 84 degree Celsius(-120 F or 189 K) and afternoon temperature was about — 29 C (— 20 F or 244 K). When the Mars comes very closes to earth, it is about 56 million kilometers from the earth. The telescope of only 7 to 10 cm aperture will show the reddish Surface, Polar ice fields, clouds and dusky,markings of the Mars. Galileo was the first Scientist who invented telescope and was the first Scientist who have observed the Mars.
Giovanni Domenico Cassini determine that the Mar's rotation period is 24 hrs 37 minutes little longer than the Earths. From early observation of 1700s and 1800s from Telescope revealed seasonal changes in the features of Mars. Observers thought dark areas were oceans called the Maria. Brighter orange areas were named deserts. Also in 1869 Father Angelo Secchi mapped Streaky marking, and they are called canals. Schiaparelli, a classical Scholar as well as astronomer, named the larger Martian dark, and light regions after historical, mythological, and geographical features of his native Mediterranean area. These names, Such as Hades, Arabia, and Libya, are Still used for the major dark, and light areas. The Mariner 9 space craft in 1971, revealed many geological structures such as craters, mountains, and Canyons. The largest Canyon complex of area nearly that of entire area of the USA, was named Valles Marineries.
Several attempts were made by the scientist to collect more and more information about the planet Mars. The first three human — made devices to reach the surface of Mars were unsuccessful Russian probes. Mars 2 crashed in the November 1971. Mars 3 landed in December 1971 but failed after 20s on the surface, another probe sent back data while parachuting through the atmosphere in 1994 but failed moments before touch down. The causes of failures may be due to dust storm during the 1971 landings.
The first successful landing on Mars was by the Viking 1 spacecraft, on July 20, 1976. The Second landing was on September 3,1976, by a Duplicate Space craft, Viking2. Mars is a desolate cold and beautiful desert planet. The reddish color of Mars was Vividly seen in photos from Viking landers. Though some rocks appeared dark gray like terrestrial Lava, most rocks and soil particles were covered with a coating of rust like, reddish iron oxide minerals. Similar iron minerals give the terrestrial deserts their familiar red-to-yellow coloration. Viking scientists were surprised to find the daytime sky of mass reddish — instead of blue. The sky color is caused by much fine red dust stirred from the surface into the air by the winds and deposited even on rock tops as it settles out of the air. The Mass has a very thin atmosphere that is mostly carbon dioxide, probably generated chiefly by the planetary degassing through volcanic activity. Winds at the two sites were usually less than 17 kph with gust exceeding 50kph. Much higher winds are believed to occur at certain seasons, however, raising clouds of dust that can be observed from Earth. Air pressure at each site was only about 0.7% that on the Earth. The polar caps on Mars give evidence that gases freeze out of its temperature on the hemisphere, permanent cap of Frozen water is seen, since even in the summer temperature is a below the freezing point of water. It is not known how much water it contains. But many scientists believe that the permanent ice cap at each pole is several kilometers thick.
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