Mars: The Red Planet
Mars is the fourth planet from the sun and in a way it, besides the earth, is probably the planet we pay the most attention to. Scientists scramble to unlock the mystery of whether there is life on mars and the public in general has always seemed to have had an interest in the Red Planet. It was named after the Roman God of War whose Greek counterpart is Ares. The most conspicous reason for this is probably that when Mars could be viewed, its deep red color gave the image of blood. Whatever secrets lie in the Red Planet will probably be uncovered soon, for our technology grows fast and so does our curiousity.
Here is some general information on Mars:
- Diameter (miles)= 4,217
- Mass (trillion trillion lbs)= 1.416
- Density (earth=1)= .71
- Gravity (earth=1)= .38
- Period of Rotation (hours)= 24.6
- Escape Velocity (mph)= 11,185
- Major Atmospheric Gas= Carbon Dioxide
- Inclination of Equator (degrees)= 25.2
- Known Moons= 2
- Mean Orbital Velocity (mph)=53,980
- Minimum Distance From Sun= 128.4
(millions of miles)
- Maximum Distance From Sun= 154.9
(millions of miles)
- Mean Distance From Sun= 141.6
(millions of miles)
- Period of Revolution (earth years)= 1.88
Here is detailed information on Mars:
Surface and Atmosphere--
Surface conditions on Mars are more similar to earth than any other planet in the solar system. However, earth's plants and animals would not survive on Mars. This is because surface temperature on Mars is much lower than that of the earth, hardly ever rising above the freezing point of water. There is evidence that Mars used to have large amounts of water on it millions of years ago, but almost none exists today. But, there is probably frozen water in Mars' polar ice caps or beneath its surface. Mars' atmosphere contains only a slight amount of oxygen, but many scientists believe that some form of life may exist on Mars even though none has been found yet.
There are several outstanding features noticeable on Mars' surface- polar caps, bright areas and dark areas. Numerous craters are present, caused by meteors crashing into the surface. Other features like canyons, gorges and what appear to be dry riverbeds have be photographed by unmanned space probes. This supports the possibility of there once having been large quantities of water flowing on the planet's surface. Mars also has volcanoes, particularly in one region near its equator. The highest volcano on Mars is twice as high as Mount Everest. Near this volcano is a huge canyon that may be a fault line.
The bright areas on Mars are reddish-brown in color and cover nearly two-thirds of the planet's surface. They are sort of like our deserts in that they are dry and covered by dust, sand and rocks. Most of the surface contains limonite , a brick colored mineral that can be vound in some of earth's desert.
The dark areas on Mars cover the other one-third of the planet. They generally appear greenish-gray or bluish-gray and form irregular patterns on the surface. These regions are called maria (seas) even though they don't contain measureable amounts of water. Throughout the year the size and color of those dark areas changes and sometimes disappear. Most astronomers believe this is due to blowing sand and dust that covers them.
Located at the planet's north and south poles are the polar caps. They appear white from the earth and probably contain larege amounts of frozen water. These caps seen to evaporate and become smaller when it is tilted toward the sun and freeze and grow when it is tilted away from the sun. The evaporation of these caps may provide some of the water vapor found in Mars' atmosphere.
Mars' atmosphere is much thinner than that surrounding the earth. It is composed mainly carbon dioxide with small amounts of nitrogen, argon, oxygen, carbon monoxide, neon, krypton and xenon. There are also tiny traces of water vapor, probably from the evaporation of the polar caps. Mars' atmospheric pressure is about 0.1 pounds per sq.in. Three types of clouds can be seen in the Martian atmosphere: Pink clouds of dust which cover much of the planet; blue clouds of ice crystals and thick white clouds which are thought to consist of water vapor.
Density and Mass--
Mars is about four-fifths as dense as the earth but its mass in only about one-tenth that of the earth. Thus, its force of gravity is only about three-eighths that of the earth. A 100 pound object on earth would weigh about 38 pounds on Mars.
Mars has two small moons that travel around it. The closest one, Phobos, is also the largest of the two. It has a diameter of about fourteen miles at the equator and about eleven miles from pole to pole. It makes its revolution around Mars in about seven and a half hours. The smaller satellite, Deimos, has a diameter of about six miles and makes its journey around Mars in thirty hours. Asaph Hall, an American astronomer, discovered both the satellites in 1877.
Flights to Mars--
In 1965, the unmanned U.S. spacecraft Mariner 4 flew about 6,118 miles from Mars. Four years later, Mariner 6 and Mariner 7 flew even closer to it. Mariner 9 orbited Mars in 1971 and 1972 where it photographed both satellites, a dust storm on the planet and various surface details. Mars 3 , a So viet probe, also orbited the planet in 1971 and released a capsule that made a soft landing on the planet's surface. However, the capsule transmitted information for only twenty seconds when it unexpectedly fell silent.
Photographs sent to the earth by Mariner 4 and Mariner 9 revealed various meteor craters on the planet's surface. These craters had never been seen in observations by astronomers from the earth. It was also found that Mars had no measureable magnetic field.
Later, on July 20, 1976, the U.S. Viking 1 landed on Mars in desertlike region near the planet's equator. The same year Viking 2 landed farther north and transmitted high-quality, close-up photographs of the surface. Both probes also analyzed Mars' atmosphere and soil to seek signs of life. Yet, in spite of these experiments, scientists are still relatively unable to determine whether lfe exists on the Red Planet.