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Mars is the fourth planet from the Sun in the solar system, named after the Roman god of war (the counterpart of the Greek Ares), on account of its blood red color as viewed in the night sky. Mars has two small moons, Phobos and Deimos, both small and oddly shaped, possibly captured asteroids. The prefix areo- refers to Mars.
Its symbol is a stylized representation of the god Mars' shield and spear: a circle with a small arrow pointing out from behind it ( Unicode: ♂).
Mars has always fascinated people. Its red, fiery appearance is mysterious and intriguing. Mars has only a quarter the surface area of the Earth and only 1/10th the mass (though because it lacks oceans the area of Mars' accessible dry land is approximately equal to that of the Earth's dry land).
Mars' atmosphereAtmosphere is the general name for a layer of gases that may surround a material body of sufficient mass. The gases are attracted by the gravity of the body, and held fast if gravity is sufficient and the atmosphere's temperature is low. Some planets cons is very thin: the surface air pressure is only 750 Pa (about 0.75% of the average on Earth). The atmosphere on Mars is 95% carbon dioxide, 3% nitrogenNitrogen is the chemical element in the periodic table that has the symbol N and atomic number 7. A common normally colorless, odorless, tasteless and mostly inert diatomic non-metal gas, nitrogen constitutes 78 percent of Earth's atmosphere and is a cons, 1.6% argonArgon was also a codename used for the KH-5 reconnaissance satellite. Argon is the chemical element in the periodic table that has the symbol Ar and atomic number 18. The third noble gas, in period 8, argon makes up about 1% of the Earth's atmosphere., with only a trace of oxygenOxygen is the chemical element in the periodic table that has the symbol O and atomic number 8. The element is very common, found not only on Earth but throughout the universe. Molecular oxygen (O, often called free oxygen on Earth is thermodynamically un and waterDrinking water This article focuses on water as we experience it every day. The water (molecule) article describes water from a scientific and technical perspective. Water is an abundant substance on Earth. It exists in many forms, such as sea, rain, and. In 20032003 is a common year starting on Wednesday (link will take you to calendar), and also: The International Year of Freshwater The European Disability Year Summary Perhaps the defining global event of the year 2003 was the Invasion of Iraq launched by the U methaneProperties General Name Methane Lewis Structure: H | H-C-H | H Chemical formula C H Formula weight 16. 04 amu Synonyms Marsh gas; Methyl hydride CAS number 74-82-8 Phase behavior Melting point 90. 5 °C) Boiling point 111 K (-162°C) Triple point 90. 48°C) was also discovered in the atmosphere by Earth-based telescopeNice Observatory. A telescope is perhaps the most important astronomical tool; such technology gathers (and focuses) electromagnetic radiation. Telescopes increase the apparent angular size of objects, as well as their apparent brightness. Galileo Galileis, confirmed in March 2004 by the Mars Express Orbiter. The presence of methane is intriguing, since as an unstable gas it indicates that there must be (or have been within the last few hundred years) a source of the gas on the planet. Volcanic activity, comet impact, and the existence of life in the form of microorganisms such as methanogens are among possible but as yet unproven sources.
Mars has an important place in human imagination due to the belief by some that life existed on Mars, due mainly to observations by Percival Lowell of Martian canals, apparently artificial linear features on the surface that he asserted were canals, and due to seasonal changes in the brightness of some areas that were thought to be caused by vegetation growth. This gave rise to many stories concerning Martians. The linear features are now known to be mostly non-existent or, in some cases, dry ancient watercourses. The color changes have been ascribed to dust storms.
In 1996, researchers studying a meteorite ( ALH84001) believed to have originated from Mars reported features which they attributed to microfossils left by life on Mars. As of 2004, this interpretation remains controversial with no consensus having emerged.
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