An Introduction to Mars Image of Mars. Smthsonian Mars is the fourth planet from the Sun and the second smallest planet in the Solar System. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts, and polar ice caps of Earth. The rotational period and seasonal cycles of Mars are likewise similar to those of Earth, as is the tilt that produces the seasons.
Besides silicon and oxygen, the most abundant elements in the Martian crust are iron, magnesiumaluminumcalciumand potassium. Surface geology Main article: Geology of Mars Mars is a terrestrial planet that consists of minerals containing silicon and oxygenmetalsand other elements that typically make up rock.
The surface of Mars is primarily composed of tholeiitic basalt although parts are more silica -rich than typical basalt and may be similar to andesitic rocks on Earth or silica glass. Regions of low albedo suggest concentrations of plagioclase feldsparwith northern low albedo regions displaying higher than normal concentrations of sheet silicates and high-silicon glass.
Parts of the southern highlands include detectable amounts of high-calcium pyroxenes. Localized concentrations of hematite and olivine have been found.
This paleomagnetism of magnetically susceptible minerals is similar to the alternating bands found on Earth's ocean floors. One theory, published in and re-examined in October with the help of the Mars Global Surveyoris that these bands suggest plate tectonic activity on Mars four billion years ago, before the planetary dynamo ceased to function and the planet's magnetic field faded.
Mars has many distinctive chemical features caused by its position in the Solar System. Elements with comparatively low boiling points, such as chlorinephosphorusand sulphurare much more common on Mars than Earth; these elements were probably pushed outward by the young Sun's energetic solar wind.
Formation of the oldest extant surfaces of Mars, 4. Noachian age surfaces are scarred by many large impact craters. The Tharsis bulge, a volcanic upland, is thought to have formed during this period, with extensive flooding by liquid water late in the period. Hesperian period named after Hesperia Planum: The Hesperian period is marked by the formation of extensive lava plains.
Amazonian period named after Amazonis Planitia: Amazonian regions have few meteorite impact craters, but are otherwise quite varied. Olympus Mons formed during this period, with lava flows elsewhere on Mars.
Geological activity is still taking place on Mars. The Athabasca Valles is home to sheet-like lava flows created about Mya.
Water flows in the grabens called the Cerberus Fossae occurred less than 20 Mya, indicating equally recent volcanic intrusions. Martian soil Exposure of silica-rich dust uncovered by the Spirit rover The Phoenix lander returned data showing Martian soil to be slightly alkaline and containing elements such as magnesiumsodiumpotassium and chlorine.
These nutrients are found in soils on Earth, and they are necessary for growth of plants. The streaks are dark at first and get lighter with age. The streaks can start in a tiny area, then spread out for hundreds of metres. They have been seen to follow the edges of boulders and other obstacles in their path.
The commonly accepted theories include that they are dark underlying layers of soil revealed after avalanches of bright dust or dust devils. Radar data from Mars Express and the Mars Reconnaissance Orbiter show large quantities of water ice at both poles July   and at middle latitudes November Huge linear swathes of scoured ground, known as outflow channelscut across the surface in about 25 places.
These are thought to be a record of erosion caused by the catastrophic release of water from subsurface aquifers, though some of these structures have been hypothesized to result from the action of glaciers or lava. It is thought to have been carved by flowing water early in Mars's history.
Features of these valleys and their distribution strongly imply that they were carved by runoff resulting from precipitation in early Mars history.
Subsurface water flow and groundwater sapping may play important subsidiary roles in some networks, but precipitation was probably the root cause of the incision in almost all cases. A number of authors have suggested that their formation process involves liquid water, probably from melting ice,   although others have argued for formation mechanisms involving carbon dioxide frost or the movement of dry dust.
Further evidence that liquid water once existed on the surface of Mars comes from the detection of specific minerals such as hematite and goethiteboth of which sometimes form in the presence of water. This forms only in the presence of acidic water, which demonstrates that water once existed on Mars.
The Phoenix lander directly sampled water ice in shallow Martian soil on July 31, This finding was derived from the ratio of water to deuterium in the modern Martian atmosphere compared to that ratio on Earth.
The amount of Martian deuterium is eight times the amount that exists on Earth, suggesting that ancient Mars had significantly higher levels of water. Results from the Curiosity rover had previously found a high ratio of deuterium in Gale Craterthough not significantly high enough to suggest the former presence of an ocean.
Other scientists caution that these results have not been confirmed, and point out that Martian climate models have not yet shown that the planet was warm enough in the past to support bodies of liquid water. These seasonal actions transport large amounts of dust and water vapor, giving rise to Earth-like frost and large cirrus clouds.
Clouds of water-ice were photographed by the Opportunity rover in Frozen carbon dioxide accumulates as a comparatively thin layer about one metre thick on the north cap in the northern winter only, whereas the south cap has a permanent dry ice cover about eight metres thick.Mars: Mars, fourth planet in the solar system in order of distance from the Sun and seventh in size and mass.
It is a periodically conspicuous reddish object in the night sky. There are intriguing clues that billions of years ago Mars was even more Earth-like than today.
Squyres, S.W. Roving Mars: Spirit, Opportunity, and the Exploration of the Red Planet It’s here: the NEW Britannica Kids website!
We’ve been busy, working hard to . In English, Mars carries a name of the Roman god of war, and is often referred to as the "Red Planet" because the reddish iron oxide prevalent on its surface gives it a reddish appearance that is distinctive among the astronomical bodies visible to the naked eye.
Course Introduction. This course is designed to enable freshmen to learn of the rich intellectual and scientific history of the exploration of Mars, starting with the early fascination of the 'red planet' in the sky, through Lowell's canals and civilizations, to the dawn of the modern era with spacecraft exploration and the involvement of.
Introduction No planet beyond Earth has been studied as intensely as Mars. Recorded observations of Mars date as far back as the era of ancient Egypt over 4, years ago, when they charted the planet's movements in the sky.
Mars is the fourth planet from the Sun and the second smallest planet in the Solar System. Named after the Roman god of war, it is often described as the “Red Planet”, as the iron oxide prevalent on its surface gives it a reddish appearance.
Mars is a terrestrial planet with a thin atmosphere.