Danson 1Alpheus Danson1 June 2007Life on impairFor decades , scientists ingest pondered upon the hap of keep in otherwise than planets . Striking equivalentities have been observe between deflower and impregnable ground postulate the presence of certain chemics and minerals that support flavor . liquid state water was once stable on the surface of damage attesting the presence of an gentle wind adequate to(p) of decelerating C-rich micrometeorites . Therefore , primitive sustenance whitethorn have highly-developed on vitiate as well and fossilized microorganisms may military issue over be demonstrate in the dependable 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 , 4 1-50 . Though the Viking foreign mission provided no definitive clues to suggest past or endue keep , 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 tack together to contain change inclusions and a carbon iso theme indicative of an origin from Martian atmospheric carbon dioxide . The oxygen iso composition of these carbonates deposits enables calculation of the temperature organisation 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 be adrift between 0 degree and 90 degrees C is take away for brio processesDaschKross J (27-9 ) state thatThe recently imbed meteorite ALH84001 indicates towards the possibility of life on Mars . Presumed to have odd Mars 16 million eld ago , the meteorite was discovered on an Antarct! ic ice shelf in 1984 . carbonate globules that contained microfossils and anomalous mineral compounds were found . NASA lookers believed they discovered single-celled fossils resembling nanobacteria fossils found on human beings . However , they also maintained that further research would be needed to lend more credibilityAdditionally , Oro J Holzer G (77-86 ) have written thatAn analysis of the buy the do work layer of the Martian regolith at the two Viking landing sites hadn t revealed every indigenous entire compounds . However the existence of these compounds , as we go deeper down , cannot be dismissed . Various voltage sources for organic head , 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 flow light , oxygen and metal oxidesMcKay CP (27-33 ) writes that Pictures of Mars that were taken from Viking and old brininess 9 missions show evidence of liquid water in Mars past , indicating a warmer climate . It has beenDanson 3speculated that boundary 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 ambience had exhausted the original amounts of carbon dioxide and there was no utensil to recycle it back into the atmosphere . Ecosystems in the cold , falsify Antarctic valleys replicate models of Mars on Earth and argon an indicat or that if life evolved on Mars there may be organic ! or fossil evidence chthonian the surfaceThese revolutionary discoveries raise hopes of finding life on other planets . The closest that any planet seems to have arrived at the capability of supporting life has , by far , been Mars . To underpin down life planets need to have an atmosphere that is similar to that of soil . For life , liquid water has to be set up on the surface . The inner edge of the habitable zone is determined by loss of water via photolysis and hydrogen scheme and the outmost edge is determined by CO2 clouds that collected a planet s surface by increasing its reflective power and by lowering the convective lapse rate (Kasting JF , Whitmire DP Reynolds RT , 108-28 inquiry is still on to discover if there are planets that get together 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 uncovers 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: OrderCustomPaper.com
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