Danson 1Alpheus Danson1 June 2007Life on impairFor decades , scientists take on pondered upon the hap of keep in some otherwise planets . Striking interchangeableities have been spy between deflower and comforting ground deprivation the presence of certain chemicals and minerals that support vitality . liquid state water was once stable on the surface of damage attesting the presence of an gentle wind candid of decelerating C-rich micrometeorites . Therefore , primitive vivification whitethorn have actual on mar as well and fossilized microorganisms may interest over be demonstrate in the climb up subsurface (Brack A Pillinger C , 313-9 . The environs of Mars 3 .5 to 4 .0 Gyr ago resembled that of the existence at this time since both(prenominal) contained liquid water (Mckay CP , 41-50 . Though the Vi king foreign mission provided no definitive clues to suggest past or endue emotional state , Martian meteorites showed evidences of conducive chemical essential law (Brack A Pillinger C , 313-9Brack A Pillinger C (313-9 ) also say thatDespite the volcanic nature of the samples , some of them have been set to contain change inclusions and a carbon iso organization indicative of an origin from Martian atmospheric carbon dioxide . The oxygen iso composition of these carbonates deposits enables calculation of the temperature judicature that existed when a fluid that dissolved the carbon dioxide was formed . Since the composition of the fluid is yet un laid , only the temperature prototypeDanson 2could be estimated . The surf between 0 degree and 90 degrees C is take away for animateness processesDaschKross J (27-9 ) state thatThe recently constitute meteorite ALH84001 indicates towards the possibility of life on Mars . Presumed to have remaining Mars 16 million histori c period ago , the meteorite was discovered ! on an Antarctic ice shelf in 1984 . change globules that contained microfossils and anomalous mineral compounds were found . NASA lookers believed they discovered single-celled fossils resembling nanobacteria fossils found on existence . However , they also maintained that just research would be needed to lend more credibilityAdditionally , Oro J Holzer G (77-86 ) have written thatAn analysis of the buy the upraise layer of the Martian regolith at the two Viking landing sites hadn t revealed both indigenous thoroughgoing compounds . However the existence of these compounds , as we go deeper down , cannot be dismissed . Various voltage sources for organic discipline , like comets and meteorites , atomic number 18 indicated by Cosmochemical considerations . The disappearance of organic matter from the top layer could have been the result of a debasement processes on the surface of Mars by destructive agents like ultraviolet depress light , oxygen and metal oxidesMcKay CP (27-33 ) writes thatPictures of Mars that were taken from Viking and old flavour 9 missions show evidence of liquid water in Mars past , indicating a warmer climate . It has beenDanson 3speculated that saltation channels and valley networks were formed 3 .5 to 4 billions years ago . This was the time when life was developing on Earth .

Presenttheories suggest that chemical reactions in Mars early glory had exhausted the original amounts of carbon dioxide and there was no weapon to recycle it back into the atmosphere . Ecosystems in the cold , fake Antarctic valleys replicate models of Mars on Earth and a re an indicator that if life evolved on Mars there ma! y be organic or fossil evidence bottom(prenominal) the surfaceThese revolutionary discoveries raise hopes of finding life on other planets . The closest that any planet seems to have arrived at the effectiveness of supporting life has , by far , been Mars . To actualise down life planets need to have an atmosphere that is similar to that of soil . For life , liquid water has to be put on the surface . The inner edge of the habitable partition off is determined by loss of water via photolysis and hydrogen execute and the outmost edge is determined by CO2 clouds that placid a planet s surface by increasing its albedo and by lowering the convective lapse rate (Kasting JF , Whitmire DP Reynolds RT , 108-28 look into is still on to discover if there are planets that adopt these criteriaDanson 4Works CitedBrack A Pillinger C , Life on Mars : chemical arguments and clues from MartianMeteorites , Extremophiles . 1998 Aug 2 (3 :313-9DaschKross J , My favorite Martians : NASA unc overs evidence of ancient life onMars , Ad Astra . 1996 Sep-Oct 8 (5 :27-9McKay CP , Past , present , and future life on Mars Gravit Space Biol Bull 1998May 11 (2 :41-50Oro J , Holzer G , The effects of ultraviolet light on the degradation of organiccompounds :a possible explanation for the absence of organic matter on Mars . Life Sci Space Res . 1979 17 :77-86McKay CP Did Mars once have martians ? Astronomy . 1993 Sep 21 :27-33Kasting JF , Whitmire DP Reynolds RT , Habitable zones around main sequencestars .Icarus , 1993 Jan , 101 (1 :108-28...If you want to get a full essay, order it on our website:
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