mars and its origin

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Introduction

Mars is the fourthplanet from theSun in theSolar System.The planet is named after theRomangod of

war,Mars.It is often described as the "Red Planet", as theiron oxide prevalent on its surface gives it a

reddish appearance.Mars is aterrestrial planet with a thinatmosphere,having surface features

reminiscent both of theimpact craters of theMoon and the volcanoes, valleys, deserts, andpolar ice

caps ofEarth.Therotational period and seasonal cycles of Mars are likewise similar to those of Earth, as

is the tilt that produces the seasons. Mars is the site ofOlympus Mons,the highest known mountain

within the Solar System, and ofValles Marineris,the largest canyon. The smoothBorealis basin in the

northern hemisphere covers 40% of the planet and may be a giant impact feature.

Until the first flyby of Mars occurred in 1965, byMariner 4,many speculated about the presence of

liquid water on the planet's surface. This was based on observed periodic variations in light and dark

patches, particularly in the polarlatitudes,which appeared to be seas and continents; long, dark

striations were interpreted by some as irrigation channels for liquid water. These straight line features

were later explained asoptical illusions,though geological evidence gathered by unmanned missions

suggest that Mars once had large-scale water coverage on its surface. In 2005, radar data revealed the

presence of large quantities of water ice at the poles, and at mid-latitudes. The Mars rover Spirit

sampled chemical compounds containing water molecules in March 2007. ThePhoenixlander directly

sampled water ice in shallow Martian soil on July 31, 2008.

Mars has twomoons,Phobos andDeimos,which are small and irregularly shaped. These may becapturedasteroids,similar to5261 Eureka,aMartian trojan asteroid.Mars is currently host to three

functional orbitingspacecraft:Mars Odyssey,Mars Express,and theMars Reconnaissance Orbiter.On

the surface are theMars Exploration RoverOpportunityand its recently decommissioned twin,Spirit,

along with several other inert landers and rovers, both successful and unsuccessful. The Phoenixlander

completed its mission on the surface in 2008. Observations byNASA's now-defunctMars Global

Surveyorshow evidence that parts of the southern polar ice cap have been receding. Observations by

NASA'sMars Reconnaissance Orbiter have revealed possible flowing water during the warmest months

on Mars.

Mars can easily be seen from Earth with the naked eye. Itsapparent magnitude reaches 3.0 abrightness surpassed only byJupiter,Venus,the Moon, and the Sun.
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Physical characteristics

Size comparison ofEarth and Mars.

Mars has approximately half theradius of Earth. It is less dense than Earth, having about 15% of Earth's

volume and 11% of themass.Itssurface area is only slightly less than the total area of Earth's dry land.

While Mars is larger and more massive thanMercury,Mercury has a higher density. This results in the

two planets having a nearly identical gravitational pull at the surfacethat of Mars is stronger by less

than 1%. Mars is also roughly intermediate in size, mass, andsurface gravity between Earth and Earth's

Moon (the Moon is about half the diameter of Mars, whereas Earth is twice; the Earth is about nine

times more massive than Mars, and the Moon one-ninth as massive). The red-orange appearance of theMartian surface is caused byiron oxide,more commonly known as hematite, or rust.

Geology

Main article:Geology of Mars

Based on orbital observations and the examination of theMartian meteorite collection, the surface of

Mars appears to be composed primarily ofbasalt.Some evidence suggests that a portion of the Martian

surface is more silica-rich than typical basalt, and may be similar toandesitic rocks on Earth; these

observations may also be explained by silica glass. Much of the surface is deeply covered by finelygrainediron oxide dust.

Although Mars has no evidence of a current structured globalmagnetic field,observations show that

parts of the planet's crust have been magnetized, and that alternating polarity reversals of its dipole

field have occurred in the past. Thispaleomagnetism of magnetically susceptible minerals has properties

that are very similar to thealternating bands found on the ocean floors of Earth.One theory, published

in 1999 and re-examined in October 2005 (with the help of theMars Global Surveyor), is that these

bands demonstrateplate tectonics on Mars fourbillion years ago, before the planetarydynamo ceased

to function and caused the planet's magnetic field to fade away.

Current models of the planet's interior imply a core region about 1,480 km in radius, consisting primarilyofiron with about 1417%sulfur.Thisiron sulfide core is partially fluid, and has twice the concentration

of the lighter elements than exist at Earth's core. The core is surrounded by a silicatemantle that

formed many of the tectonic and volcanic features on the planet, but now appears to be inactive. The

average thickness of the planet's crust is about 50 km, with a maximum thickness of 125 km. Earth's

crust, averaging 40 km, is only one third as thick as Mars crust, relative to the sizes of the two planets.
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During theSolar System's formation,Mars was created out of theprotoplanetary disk that orbited the

Sun as the result of astochastic process of run-away accretion. Mars has many distinctive chemical

features caused by its position in the Solar System. Elements with comparatively low boiling points such

as chlorine, phosphorus and sulphur are much more common on Mars than Earth; these elements were

probably removed from areas closer to the Sun by the young Sun's powerfulsolar wind.

After the formation of the planets, all were subjected to the "Late Heavy Bombardment". About 60% of

the surface of Mars shows an impact record from that era. Much of the rest of the surface of Mars is

probably underlain by immense impact basins that date from this timethere is evidence of an

enormous impact basin in the northern hemisphere of Mars, spanning 10,600 km by 8,500 km, or

roughly four times larger than the Moon'sSouth Pole-Aitken basin,the largest impact basin yet

discovered. This theory suggests that Mars was struck by aPluto-sized body about four billion years ago.

The event, thought to be the cause of theMartian hemispheric dichotomy,created the smoothBorealis

basin that covers 40% of the planet.

The geological history of Mars can be split into many periods, but the following are the three primary

periods:

Noachian period(named afterNoachis Terra): Formation of the oldest extant surfaces of Mars,4.5 billion years ago to 3.5 billion years ago. Noachian age surfaces are scarred by many large

impact craters. TheTharsis 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): 3.5 billion years ago to 2.93.3 billion yearsago. The Hesperian period is marked by the formation of extensive lava plains.

Amazonian period(named afterAmazonis Planitia): 2.93.3 Gyr ago billion years ago to present.Amazonian regions have fewmeteorite impact craters, but are otherwise quite varied.Olympus

Mons formed during this period, along with lava flows elsewhere on Mars.

Top down view ofOlympus Mons,the highest known mountain

in the solar system

Some geological activity is still taking place on Mars. The

Athabasca Valles is home to sheet-like lava flows up to about 200

Mya.Water flows in the grabens called theCerberus Fossae

occurred less than 20 Mya, indicating equally recent volcanicintrusions. On February 19, 2008, images from theMars

Reconnaissance Orbitershowed evidence of an avalanche from a

700 m high cliff.
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Soil

Main article:Martian soil

ThePhoenixlander returned data showing Martian soil to be slightly

alkaline and containing elements such asmagnesium,sodium,potassium

andchloride.These nutrients are found in gardens on Earth, and are

necessary for growth of plants. Experiments performed by the Lander

showed that the Martian soil has abasicpH of 8.3, and may contain

traces of thesaltperchlorate.

Annotated image of Tharsis Tholus dark streak, as seen byHirise.It is

located in the middle left of this picture.Tharsis Tholus is just off to the

right.

Streaks are common across Mars and new ones appear frequently on

steep slopes of craters, troughs, and valleys. The streaks are dark at first

and get lighter with age. Sometimes the streaks start in a tiny area which

then spreads out for hundreds of meters. They have also 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. Several explanations have been put

forward, some of which involvewater or even the growth of organisms.

Hydrology

Main article:Water on MarsMicroscopic photo taken byOpportunityshowing a gray

hematiteconcretion,indicative of the past presence of liquid

water.

Liquid water cannot exist on the surface of Mars due to low

atmospheric pressure, except at the lowest elevations for short

periods. The two polar ice caps appear to be made largely of

water. The volume of water ice in the south polar ice cap, if

melted, would be sufficient to cover the entire planetary surface

to a depth of 11 meters. Apermafrost mantle stretches from the

pole to latitudes of about 60.

Large quantities of water ice are thought to be trapped underneath the thickcryosphere of Mars. Radar

data fromMars Expressand theMars Reconnaissance Orbitershow large quantities of water ice both at

the poles (July 2005) and at mid-latitudes (November 2008). The Phoenix lander directly sampled water

ice in shallow Martian soil on July 31, 2008.
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Landforms visible on Mars strongly suggest that liquid water has at least at times existed on the planet's

surface. Huge linear swathes of scoured ground, known asoutflow channels,cut across the surface in

around 25 places. These are thought to record erosion which occurred during the catastrophic release of

water from subsurface aquifers, though some of these structures have also been hypothesized to result

from the action of glaciers or lava. The youngest of these channels are thought to have formed as

recently as only a few million years ago. Elsewhere, particularly on the oldest areas of the Martian

surface, finer-scale, dendriticnetworks of valleys are spread across significant proportions of the

landscape. Features of these valleys and their distribution very strongly imply that they were carved by

runoff resulting from rain or snow fall in early Mars history. Subsurface water flow andgroundwater

sapping may play important subsidiary roles in some networks, but precipitation was probably the root

cause of the incision in almost all cases.

There are also thousands of features along crater and canyon walls that appear similar to terrestrial

gullies.The gullies tend to be in the highlands of the southern hemisphere and to face the Equator; all

are pole ward of 30 latitude. A number of authors have suggested that their formation process

demands the involvement of liquid water, probably from melting ice, although others have argued forformation mechanisms involving carbon dioxide frost or the movement of dry dust. No partially

degraded gullies have formed by weathering and no superimposed impact craters have been observed,

indicating that these are very young features, possibly even active today.

Other geological features, such asdeltas andalluvial fans preserved in craters, also argue very strongly

for warmer, wetter conditions at some interval or intervals in earlier Mars history. Such conditions

necessarily require the widespread presence of craterlakes across a large proportion of the surface, for

which there is also independent mineralogical, sedimentological and geomorphological evidence. Some

authors have even gone so far as to argue that at times in the Martian past, much of the low northern

plains of the planet were covered with a true ocean hundreds of meters deep, though this remainscontroversial.

Further evidence thatliquid water once existed on the surface of Mars comes from the detection of

specific minerals such ashematite andgoethite,both of which sometimes form in the presence of

water. Some of the evidence believed to indicate ancient water basins and flows has been negated by

higher resolution studies by the Mars Reconnaissance Orbiter. In 2004, Opportunitydetected the

mineraljarosite.This forms only in the presence of acidic water, which demonstrates that water once

existed on Mars.
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Polar capsViking Orbiter's view of the northern ice cap of Mars

South polar cap in 2000

Mars has two permanent polar ice caps. During a pole's winter,

it lies in continuous darkness, chilling the surface and causing

thedeposition of 2530% of the atmosphere into slabs ofCO2

ice (dry ice). When the poles are again exposed to sunlight, the

frozen CO2sublimes,creating enormous winds that sweep off

the poles as fast as 400 km/h. These seasonal actions transport

large amounts of dust and water vapor, giving rise to Earth-like

frost and largecirrus clouds.Clouds of water-ice were photographed by theOpportunityrover in 2004.

The polar caps at both poles consist primarily of water ice. Frozen carbon dioxide accumulates as a

comparatively thin layer about one meter thick on the north cap in the northern winter only, while the

south cap has a permanent dry ice cover about eight meters thick. The northern polar cap has a

diameter of about 1,000 kilometers during the northern Mars summer, and contains about 1.6 million

cubic km of ice, which if spread evenly on the cap would be 2 km thick. (This compares to a volume of

2.85 million cubic km (km3) for theGreenland ice sheet.) The southern polar cap has a diameter of

350 km and a thickness of 3 km. The total volume of ice in the south polar cap plus the adjacent layered

deposits has also been estimated at 1.6 million cubic km. Both polar caps show spiral troughs, which are

believed to form as a result of differential solar heating, coupled with the sublimation of ice and

deposition of water vapor.

The seasonal frosting of some areas near the southern ice cap results

in the formation of transparent 1 meter thick slabs of dry ice above the

ground. As the region warms with the arrival of spring, pressure from

subliming CO2builds up under a slab, elevating and ultimately

rupturing it. This leads togeyser-like eruptions of CO2gas mixed with

dark basaltic sand or dust. This process is rapid, observed happening in

the space of a few days, weeks or months, a rate of change rather

unusual in geologyespecially for Mars. The gas rushing underneath a

slab to the site of a geyser carves a spider-like pattern of radial

channels under the ice.
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Tectonic sites

Theshield volcano,Olympus Mons (Mount Olympus), at 27 km is the highest known mountain in the

Solar System. It is an extinct volcano in the vast upland regionTharsis,which contains several other large

volcanoes. Olympus Mons is over three times the height ofMount Everest,which in comparison stands

at just over 8.8 km.

The large canyon,Valles Marineris (Latin forMariner Valleys, also known as Agathadaemon in the old

canal maps), has a length of 4,000 km and a depth of up to 7 km. The length of Valles Marineris is

equivalent to the length of Europe and extends across one-fifth the circumference of Mars. By

comparison, theGrand Canyon on Earth is only 446 km long and nearly 2 km deep. Valles Marineris was

formed due to the swelling of the Tharsis area which caused the crust in the area of Valles Marineris to

collapse. Another large canyon isMa'adim Vallis (Ma'adimisHebrew for Mars). It is 700 km long and

again much bigger than the Grand Canyon with a width of 20 km and a depth of 2 km in some places. It

is possible that Ma'adim Vallis was flooded with liquid water in the past.

Caves

THEMIS image of probable Mars cave entrances, informally

named (A) Dena, (B) Chloe, (C) Wendy, (D) Annie, (E) Abby (left)

and Nikki, and (F) Jeanne.

Images from theThermal Emission Imaging System (THEMIS) aboard NASA'sMars Odyssey orbiter have

revealed seven possiblecave entrances on the flanks of theArsia Mons volcano. The caves, named after

loved ones of their discoverers, are collectively known as the "seven sisters." Cave entrances measure

from 100 m to 252 m wide and they are believed to be at least 73 m to 96 m deep. Because light does

not reach the floor of most of the caves, it is likely that they extend much deeper than these lower

estimates and widen below the surface. "Dena" is the only exception; its floor is visible and was

measured to be 130 m deep. The interiors of these caverns may be protected from micrometeoroids, UV

radiation,solar flares and high energy particles that bombard the planet's surface.
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Atmosphere

Main article:Atmosphere of Mars

The tenuous atmosphere of Mars, visible on the horizon in this low-orbit

photo

Mars lost itsmagnetosphere 4 billion years ago, so thesolar wind interacts

directly with the Martianionosphere,lowering the atmospheric density by

stripping away atoms from the outer layer. BothMars Global Surveyor and

Mars Express have detected these ionized atmospheric particles trailing off

into space behind Mars. Compared to Earth, theatmosphere of Mars is

quite rarefied.Atmospheric pressure on the surface ranges from a low of

30Pa (0.030kPa)onOlympus Mons to over 1,155 Pa (1.155 kPa) in theHellas Planitia,with a mean

pressure at the surface level of 600 Pa (0.60 kPa). The surface pressure of Mars at its thickest is equal to

the pressure found 35 km above the Earth's surface. This is less than 1% of the Earth's surface pressure(101.3 kPa). Thescale height of the atmosphere is about 10.8 km, which is higher than Earth's (6 km)

because the surface gravity of Mars is only about 38% of Earth's, an effect offset by both the lower

temperature and 50% higher average molecular weight of the atmosphere of Mars.

The atmosphere on Mars consists of 95%carbon dioxide,3%nitrogen,1.6%argon and contains traces of

oxygen and water. The atmosphere is quite dusty, containing particulates about 1.5m in diameter

which give the Martian sky atawny color when seen from the surface.

Climate

Mars fromHubble Space Telescope October 28, 2005 with

dust storm visible.

Main article:Climate of Mars

Of all the planets in the Solar System, the seasons of Mars are

the most Earth-like, due to the similar tilts of the two planets'

rotational axes. The lengths of the Martian seasons are about

twice those of Earth's, as Mars greater distance from the Sun

leads to the Martian year being about two Earth years long. Martian surface temperatures vary from

lows of about 87 C (125F) during the polar winters to highs of up to 5 C (23F) in summers. The

wide range in temperatures is due to the thin atmosphere which cannot store much solar heat, the low
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atmospheric pressure, and the lowthermal inertia of Martian soil. The planet is also 1.52 times as far

from the sun as Earth, resulting in just 43% of the amount of sunlight.

If Mars had an Earth-like orbit, its seasons would be similar to Earth's because itsaxial tilt is similar to

Earth's. The comparatively large eccentricity of the Martian orbit has a significant effect. Mars is near

perihelion when it is summer in the southern hemisphere and winter in the north, and nearaphelionwhen it is winter in the southern hemisphere and summer in the north. As a result, the seasons in the

southern hemisphere are more extreme and the seasons in the northern are milder than would

otherwise be the case. The summer temperatures in the south can reach up to 30 C (86 F) warmer

than the equivalent summer temperatures in the north.

Mars also has the largestdust storms in our Solar System. These can vary from a storm over a small

area, to gigantic storms that cover the entire planet. They tend to occur when Mars is closest to the Sun,

and have been shown to increase the global temperature.
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Moons

Main articles:Moons of Mars,Phobos (moon),andDeimos (moon)

Phobos in color byMars Reconnaissance Orbiter HiRISE,on March 23, 2008

Deimos in color on February 21, 2009 by the same (not to scale)

Mars has two relatively small natural moons,Phobos andDeimos,which orbit close to the planet.

Asteroid capture is a long-favored theory but their origin remains uncertain. Both satellites were

discovered in 1877 byAsaph Hall,and are named after the charactersPhobos (panic/fear) andDeimos

(terror/dread) who, inGreek mythology,accompanied their fatherAres,god of war, into battle. Ares

was known as Mars to the Romans.

From the surface of Mars, the motions of Phobos and Deimos appear very different from that of our

own moon. Phobos rises in the west, sets in the east, and rises again in just 11 hours. Deimos, being only

just outsidesynchronous orbitwhere the orbital period would match the planet's period of rotation

rises as expected in the east but very slowly. Despite the 30 hour orbit of Deimos, it takes 2.7 days to set

in the west as it slowly falls behind the rotation of Mars, then just as long again to rise.

Because the orbit of Phobos is below synchronous altitude, thetidal forces from the planet Mars are

gradually lowering its orbit. In about 50 million years it will either crash into Mars surface or break up

into a ring structure around the planet.

The origin of the two moons is not well understood. Their low albedo andcarbonaceous chondrite

composition have been regarded as similar to asteroids, supporting the capture theory. The unstable

orbit of Phobos would seem to point towards a relatively recent capture. But both havecircular orbits,

very near the equator, which is very unusual for captured objects and the required capture dynamics are

complex. Accretion early in the history of Mars is also plausible but would not account for a composition

resembling asteroids rather than Mars itself, if that is confirmed.
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A third possibility is the involvement of a third body or some kind of impact disruption. More recent

lines of evidence for Phobos having a highly porous interior and suggesting a composition containing

mainlyphyllosilicates and other minerals known from Mars, point toward an origin of Phobos from

material ejected by an impact on Mars that reaccreted in Martian orbit, similar to theprevailing theory

for the origin of Earth's moon. While theVNIR spectra of the moons of Mars resemble those of outer

belt asteroids, thethermal infrared spectra of Phobos are reported to be inconsistent withchondrites of

any class.

ExplorationMain article:Exploration of Mars

Viking Lander 2 site May 1979 Viking Lander 1 site February 1978

Spirit's lander on Mars, 2004 View from thePhoenix lander, 2008
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Search for lifeMain article:Life on Mars

The current understanding ofplanetary habitabilitythe ability of a

world to develop and sustain lifefavors planets that have liquid water

on their surface. This most often requires that the orbit of a planet lie

within thehabitable zone,which for the Sun currently extends from

just beyond Venus to about thesemi-major axis of Mars. During

perihelion Mars dips inside this region, but the planet's thin (low-pressure) atmosphere prevents liquid

water from existing over large regions for extended periods. The past flow of liquid water demonstrates

the planet's potential for habitability. Some recent evidence has suggested that any water on the

Martian surface may have been too salty and acidic to support regular terrestrial life.

The lack of a magnetosphere and extremely thin atmosphere of Mars are a challenge: the planet has

littleheat transfer across its surface, poor insulation against bombardment of thesolar wind and

insufficient atmospheric pressure to retain water in a liquid form (water instead sublimates to a gaseous

state). Mars is also nearly, or perhaps totally, geologically dead; the end of volcanic activity has

apparently stopped the recycling of chemicals and minerals between the surface and interior of the

planet.

Evidence suggests that the planet was once significantly more habitable than it is today, but whether

livingorganisms ever existed there remains unknown. TheViking probes of the mid-1970s carried

experiments designed to detect microorganisms in Martian soil at their respective landing sites and had

positive results, including a temporary increase of CO2production on exposure to water and nutrients.

This sign of life was later disputed by some scientists, resulting in a continuing debate, with NASA

scientistGilbert Levin asserting that Viking may have found life. A re-analysis of the Viking data, in lightof modern knowledge ofextremophile forms of life, has suggested that the Viking tests were not

sophisticated enough to detect these forms of life. The tests could even have killed a (hypothetical) life

form. Tests conducted by the Phoenix Mars lander have shown that the soil has a veryalkalinepH and it

contains magnesium, sodium, potassium and chloride. The soil nutrients may be able to support life but

life would still have to be shielded from the intense ultraviolet light.

At theJohnson space center lab,some fascinating shapes have been found in the Martianmeteorite

ALH84001.Some scientists propose that these geometric shapes could be fossilized microbes extant on

Mars before the meteorite was blasted into space by a meteor strike and sent on a 15 million-year

voyage to Earth. An exclusively inorganic origin for the shapes has also been proposed.

Small quantities ofmethane andformaldehyde recently detected by Mars orbiters are both claimed to

be hints for life, as thesechemical compounds would quickly break down in the Martian atmosphere. It

is remotely possible that these compounds may instead be replenished by volcanic or geological means

such asserpentinization.
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Intelligent "Martians"

An 1893 soap ad playing on the popular idea that Mars was

populated.

Main article:Mars in fiction

The popular idea that Mars was populated by intelligent

Martians exploded in the late 19th century.Schiaparelli's "canali"

observations combined withPercival Lowell's books on the

subject put forward the standard notion of a planet that was a

drying, cooling, dying world with ancient civilizations

constructing irrigation works.

Many other observations and proclamations by notable personalities added to what has been termed

"Mars Fever". In 1899 while investigating atmospheric radio noise using his receivers in his Colorado

Springs lab, inventorNikola Tesla observed repetitive signals that he later surmised might have been

radio communications coming from another planet, possibly Mars. In a 1901 interview Tesla said:

It was some time afterward when the thought flashed upon my mind that the disturbances I had

observed might be due to an intelligent control. Although I could not decipher their meaning, it was

impossible for me to think of them as having been entirely accidental. The feeling is constantly growing

on me that I had been the first to hear the greeting of one planet to another.

Mars has become a kind of mythic arena onto which we have projected our Earthly hopes and fears.

Martian tripod illustration from the 1906 French edition of The War of the Worlds by H.G. Wells.

The depiction of Mars in fiction has been stimulated by its dramatic red

color and by nineteenth century scientific speculations that its surface

conditions not only might support life, but intelligent life. Thus originated

a large number ofscience fiction scenarios, among which isH. G. Wells'

The War of the Worlds,published in 1898, in which Martians seek to

escape their dying planet by invading Earth. A subsequent USradio

adaptation of The War of the Worldson October 30, 1938 byOrson

Welles was presented as a live news broadcast, and became notorious for

causing a public panic when many listeners mistook it for the truth.

Influential works includedRay Bradbury'sThe Martian Chronicles,in
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which human explorers accidentally destroy a Martian civilization,Edgar Rice Burroughs'Barsoom

series,C. S. Lewis'novelOut of the Silent Planet(1938), and a number ofRobert A. Heinlein stories

before the mid-sixties.

AuthorJonathan Swift made reference to the moons of Mars, about 150 years before their actual

discovery byAsaph Hall,detailing reasonably accurate descriptions of their orbits, in the 19th chapter ofhis novelGulliver's Travels.

A comic figure of an intelligent Martian,Marvin the Martian,appeared on television in 1948 as a

character in theLooney Tunesanimated cartoons ofWarner Brothers,and has continued as part of

popular culture to the present.

After theMariner andViking spacecraft had returned pictures of Mars as it really is, an apparently

lifeless and canal-less world, these ideas about Mars had to be abandoned and a vogue for accurate,

realist depictions of human colonies on Mars developed, the best known of which may beKim Stanley

Robinson'sMarstrilogy.Pseudo-scientific speculations about the Face on Mars and other enigmatic

landmarks spotted byspace probes have meant that ancient civilizations continue to be a popular

theme in science fiction, especially in film.

The theme of a Martian colony that fights for independence from Earth is a major plot element in the

novels ofGreg Bear as well as the movieTotal Recall(based on a short story byPhilip K. Dick)and the

television seriesBabylon 5.Some video games also use this element, includingRed Factionand theZone

of the Endersseries. Mars (and its moons) were also the setting for the popularDoomvideo game

franchise and the laterMartian Gothic.
http://en.wikipedia.org/wiki/Edgar_Rice_Burroughshttp://en.wikipedia.org/wiki/Barsoomhttp://en.wikipedia.org/wiki/Barsoomhttp://en.wikipedia.org/wiki/Barsoomhttp://en.wikipedia.org/wiki/Barsoomhttp://en.wikipedia.org/wiki/C._S._Lewishttp://en.wikipedia.org/wiki/Out_of_the_Silent_Planethttp://en.wikipedia.org/wiki/Out_of_the_Silent_Planethttp://en.wikipedia.org/wiki/Out_of_the_Silent_Planethttp://en.wikipedia.org/wiki/Robert_A._Heinleinhttp://en.wikipedia.org/wiki/Jonathan_Swifthttp://en.wikipedia.org/wiki/Asaph_Hallhttp://en.wikipedia.org/wiki/Gulliver%27s_Travelshttp://en.wikipedia.org/wiki/Gulliver%27s_Travelshttp://en.wikipedia.org/wiki/Gulliver%27s_Travelshttp://en.wikipedia.org/wiki/Marvin_the_Martianhttp://en.wikipedia.org/wiki/Looney_Tuneshttp://en.wikipedia.org/wiki/Animated_cartoonshttp://en.wikipedia.org/wiki/Warner_Brothershttp://en.wikipedia.org/wiki/Mariner_programhttp://en.wikipedia.org/wiki/Viking_programhttp://en.wikipedia.org/wiki/Kim_Stanley_Robinsonhttp://en.wikipedia.org/wiki/Kim_Stanley_Robinsonhttp://en.wikipedia.org/wiki/Mars_trilogyhttp://en.wikipedia.org/wiki/Mars_trilogyhttp://en.wikipedia.org/wiki/Mars_trilogyhttp://en.wikipedia.org/wiki/Space_probehttp://en.wikipedia.org/wiki/Greg_Bearhttp://en.wikipedia.org/wiki/Total_Recallhttp://en.wikipedia.org/wiki/Total_Recallhttp://en.wikipedia.org/wiki/Total_Recallhttp://en.wikipedia.org/wiki/Philip_K._Dickhttp://en.wikipedia.org/wiki/Babylon_5http://en.wikipedia.org/wiki/Babylon_5http://en.wikipedia.org/wiki/Babylon_5http://en.wikipedia.org/wiki/Red_Factionhttp://en.wikipedia.org/wiki/Red_Factionhttp://en.wikipedia.org/wiki/Red_Factionhttp://en.wikipedia.org/wiki/Zone_of_the_Endershttp://en.wikipedia.org/wiki/Zone_of_the_Endershttp://en.wikipedia.org/wiki/Zone_of_the_Endershttp://en.wikipedia.org/wiki/Zone_of_the_Endershttp://en.wikipedia.org/wiki/Doom_%28video_game%29http://en.wikipedia.org/wiki/Doom_%28video_game%29http://en.wikipedia.org/wiki/Doom_%28video_game%29http://en.wikipedia.org/wiki/Martian_Gothichttp://en.wikipedia.org/wiki/Martian_Gothichttp://en.wikipedia.org/wiki/Martian_Gothichttp://en.wikipedia.org/wiki/Martian_Gothichttp://en.wikipedia.org/wiki/Doom_%28video_game%29http://en.wikipedia.org/wiki/Zone_of_the_Endershttp://en.wikipedia.org/wiki/Zone_of_the_Endershttp://en.wikipedia.org/wiki/Red_Factionhttp://en.wikipedia.org/wiki/Babylon_5http://en.wikipedia.org/wiki/Philip_K._Dickhttp://en.wikipedia.org/wiki/Total_Recallhttp://en.wikipedia.org/wiki/Greg_Bearhttp://en.wikipedia.org/wiki/Space_probehttp://en.wikipedia.org/wiki/Mars_trilogyhttp://en.wikipedia.org/wiki/Kim_Stanley_Robinsonhttp://en.wikipedia.org/wiki/Kim_Stanley_Robinsonhttp://en.wikipedia.org/wiki/Viking_programhttp://en.wikipedia.org/wiki/Mariner_programhttp://en.wikipedia.org/wiki/Warner_Brothershttp://en.wikipedia.org/wiki/Animated_cartoonshttp://en.wikipedia.org/wiki/Looney_Tuneshttp://en.wikipedia.org/wiki/Marvin_the_Martianhttp://en.wikipedia.org/wiki/Gulliver%27s_Travelshttp://en.wikipedia.org/wiki/Asaph_Hallhttp://en.wikipedia.org/wiki/Jonathan_Swifthttp://en.wikipedia.org/wiki/Robert_A._Heinleinhttp://en.wikipedia.org/wiki/Out_of_the_Silent_Planethttp://en.wikipedia.org/wiki/C._S._Lewishttp://en.wikipedia.org/wiki/Barsoomhttp://en.wikipedia.org/wiki/Barsoomhttp://en.wikipedia.org/wiki/Edgar_Rice_Burroughs


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Although Mars doesnt have active plate tectonics, and its volcanism ended millions of years ago, the

planet is much more similar toEarth andVenus,and different to the Moon andMercury.Mars is the

only other world in the Solar System that has a transparent atmosphere, and surface conditions that

could be considered somewhat habitable.
http://www.universetoday.com/14367/earth/http://www.universetoday.com/14069/venus/http://www.universetoday.com/13943/mercury/http://www.universetoday.com/13943/mercury/http://www.universetoday.com/14069/venus/http://www.universetoday.com/14367/earth/


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Mars In Culture

Mars [Greek: Ares], Roman god of war (fourth planet from the sun).

Like a badge of blood in the sky, the Red Planet has long

stood for the gods of war.

In cultureMain article:Mars in culture

Mars is named after theRomangod of war.In different cultures, Mars

represents masculinity and youth. Its symbol, a circle with an arrow

pointing out to the upper right, is also used as a symbol for the male

gender.

It seems natural that the Greeks named the fourth planet after Ares, since the fourth planet shines with

a red color, resembling blood, which is appropriate for the god of war. The Romans identified their god

of war, Mars, with the Greek Ares, so now we know the planet as Mars. Mars was the Roman war god;

his shield and spear form the planets symbol. He was one of the most important of the Roman gods and

an entire month of the year was dedicated to him. We still call the third month of the year, March, in his

honor. He was also a god of agriculture before becoming associated with Ares. The month was so named

because Mars, the patron god of the Romans, was a war-god, and spring campaigns usually began about

that time. The Roman year once began with March before it became January. He is characterized as the

god who took a savage delight in slaughter, and the hordes of slain upon the battlefield filled him with a

fierce joy. In the poems of Homer, there are such epithets as these applied to him: scourge of mortals,

piercer of shields, the bloodstained one. The Romans were well-known as a warlike people; therefore, it

is not strange that Mars became their patron god. They built temples for him and honored him by many

celebrations during the year. One of the most famous parts of the city of Rome was called the Field of

Mars (Campus Martius), and it was here that the army was reviewed and the spoils of war dedicated

after the return of the armies from some successful campaign. The word martial, pertaining to war,

came from Mars, the god of war.
http://en.wikipedia.org/wiki/Mars_in_culturehttp://en.wikipedia.org/wiki/Ancient_Romehttp://en.wikipedia.org/wiki/Mars_%28mythology%29http://en.wikipedia.org/wiki/Mars_%28mythology%29http://en.wikipedia.org/wiki/Ancient_Romehttp://en.wikipedia.org/wiki/Mars_in_culture


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Mars origin according to an eye witness

For the truth about the origin of anything, it helps to have a reliable eye-witness record. Such a record

always outweighs any circumstantial evidence that might be interpreted in another way. Genesis claims

to be a witness of One who was therethe Creator.Genesis 1:1419:

14And God said, Let there be lights in the expanse of the heavens to divide the day from the night; and

let them be for signs, and for seasons, and for days, and years:

15And let them be for lights in the expanse of the heavens to give light upon the earth: and it was so.

16And God made two great lights; the greater light to rule the day, and the lesser light to rule the night:

he made the stars also

19And the evening and the morning were the fourth day.

The Hebrew word for stars, kkbm, refers to any bright object in the sky, so includes objectsthat become shooting stars (meteors), planets ofour solar system, and by extension, any planets

around other stars. So Mars was created on Day 4 of Creation Week, three days after Earth, about 6,000

years ago.

Mars is an intriguing red heavenly object, created as a sign and a marker of times. And while many have

hoped for life, its an inhospitable, cold, dry world. Yet there is good evidence that it had huge flooding.

Since Mars is not that much further from the sun than Earth, and is freezing, it shows how finely God

tuned the earths orbit to supportlife.
http://www.biblegateway.com/bible?language=english&version=ESV&passage=Genesis%201:14%E2%80%9319http://www.biblegateway.com/bible?language=english&version=ESV&passage=Genesis%201:14%E2%80%9319http://www.biblegateway.com/bible?language=english&version=ESV&passage=Genesis%201:14%E2%80%9319http://www.biblegateway.com/bible?language=english&version=ESV&passage=Genesis%201:14%E2%80%9319

mars and its origin

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