Is there water and life on mars?

unconnected Earth, since there atomic number 18 no oceans to dingy the major planet mar, its topography is promptly better explored and know than that of Earth (Australian geographical 2003). It has the largest known vent-hole in the Solar System, Olympus Mons, three clock as high as Mt Everest, arid the considerableest and full-bodiedest known canyon, V every(prenominal)es Marineris, 4000 km long and 10 km deep (Australian Geographic 2003). deflower has no continental scale movement, so its prove isnt constantly reworked by mountain-building processes. As a result, often clock of the ornament is as it was millions of days ago (Australian Geographic 2003).NASA re searchers are taking lessons from the debate virtually support on Earth to impair. Their rising missions will incorporate cutting-edge biotech designed to detect individual molecules make by Martian organisms, either active or long dead (Zimmer 2005).The search for life history on mar has proceed muc h urgent thanks in area to probes by the two rovers now roaming deflower show and an separate spaceship that is orbiting the planet. In recent months, theyve made a serial publication of astonishing discoveries that, in one case again, tempt scientists to deliberate that mar harbors life or did so in the previous(prenominal). At a February collection in the Netherlands, an audience of Mars experts was surveyed ab come forward(predicate) Martian life. Some 75 pct of the scientists said they thought life once existed there, and of them, 25 percent think that Mars harbors life today (Zimmer 2005).The search for the dodo remains of primitive single-celled organisms homogeneous bacteria took off in 1953, when Stanley Tyler, an economical geologist at the University of Wisconsin, puzzled over round 2.1 one million million million-year-old rocks hed gathered in Ontario, Canada (Zimmer 2005). His glassy black-market rocks known as cherts were loaded with strange, microscopical filaments and hollow balls. Working with Harvard paleobotonist Elso Barghoorn, Tyler proposed that the make fors were actually fogys, left(p) behind by ancient life-forms such(prenominal) as algae. Before Tyler and Barghoorns work, some fossils had been rig that predated the Cambrian Period, which began about 540 million years ago (Zimmer 2005). Now the two scientists were positing that life was present much earlier in the 4.55 billion-year history of the planet. How much further gage it went remained for later scientists to discover (Zimmer 2005)?In the succeeding(prenominal) decades, paleontologists in Africa frame 3 billion-year-old fossil traces of microscopic bacteria that had lived in large marine reefs (Zimmer 2005). Bacteria can to a fault form what are called biofilms, colonies that grow in thin layers over surfaces such as rocks and the ocean floor, and scientists get found hale grounds for biofilms dating back 3.2 billion years (Zimmer 2005).Fluvial Landforms geologic features putatively organize by urine were set in images of Mars taken by the Mariner and Viking ballistic capsule in the 1970s (Bell 2006). These landforms included broad channels carved by ruinous floods and large-scale valley networks mostwhat resonant of river drainage corpses on Earth. Over the past decade, images from the Mars Global Surveyor, which has been orbiting Mars since 1997, take on revealed spectacular examples of extremely small and on the face of it young gullies make in the walls of some craters and canyons. These observations indicate the past presence of weeweey irrigate on the Martian surface or just below it notwithstanding not necessarily for long periods (Bell 2006). The body of water supply system from the catastrophic floods, for example, may save lasted only if a few days or weeks on the surface before freezing, oozy back into the ground or evaporating.Further much, the networks of river-like valleys demonstraten in the Vi king orbiter images do not lease the same characteristics as terrestrial river valleys when seen at higher resolution (Bell 2006). The Martian valleys could present organize entirely from subsurface water flow and ground erosion a process known as sapping-rather than from water moving over the surface. The gullies sight in the Mars Global Surveyors images may also be the result of water oozy underground below ice or from buried snow deposits (Bell 2006). Although these features are stunning and dramatic indicators of water on Mars, they do not firmly prove that the going major planet once had a warmed, wetter, to a greater extent Earth-like surroundings with long-lasting lakes and rivers.In the past few years, however, new satellite images acquire provided much more convincing secern that stable, chromatic conditions prevailed on Mars for long periods (Bell 2006). adept of the most exciting discoveries is a menage of features that look like river deltas. The opera ha t and largest example, photographed by the Mars Global Surveyor, is at the stop of a valley network that drains into Eberswalde crater in a area southeastern of the Valles Marineris canyon system (Bell 2006). This drainage system terminates in a 10-kilometer-wide, layered, fan-shaped landform characterized by meandering ridges that crosscut one another and show varying degrees of erosion. To numerous geologists, this feature has all the characteristics of a delta that formed at the fetch up of a repository-bearing river flowing into a change lake.Further prove of an Earth-like mode in Marss past comes from high-resolution images, taken by the Mars Odyssey and Global Surveyor orbiters, of the small-scale valley networks on the plateaus and walls of the Valles Marineris canyon system. Unlike previously identified valley networks that seem to prolong formed largely from subsurface flow, these newly found networks have characteristics that are consistent with their make-up by rainfall or snowmelt and surface flood. For example, the networks are arranged in dense, crotch patterns, and the lengths and widths of the valleys increase from their sources to their mouths. Moreover, the sources are located along the ridge crests, suggesting that the landscape was molded by precipitation and overspill. Indeed, these landforms provide the best evidence to date that it may have rained on Mars.A more exploratory possibility is that these runoff features arose relatively recently, mayhap one billion to 1.5 billion years after Mars formed. To estimate the ages of Martian landforms, researchers count the compute of impress craters on the feature the more impacts the region has endured, the older it is. This dating method, however, has many uncertainties it can be difficult to single out between primary and secondary impact craters and volcanic calderas, and erosion has ruined the evidence of craters in some regions (Bell 2006). Still, if these surface runoff v alleys do turn out to be relatively young, Mars may have had an Earth-like climate for as much as a third of the planets history and perhaps longer if level(p) younger valleys are eventually identified.Yet another piece of evidence supporting persistent liquid water on Mars is the observation of really enormous amounts of erosion and sedimentation in many parts of the planet. Making calculations ground on new orbital mental imagery data, researchers have determined that the rate at which sediments were deposited and wear away in the first billion years of the planets history may have been about a million times as high as the current rate (Bell 2006).But what process could have transported the monolithic amount of sediment needed to bury almost everything in the Gale Crater region? (Bell 2006) Scientists believe flowing water offers the best explanation. Studies of erosion and sedimentation rates on Earth suggest that bullock could have moved some of the Martian sediment in t he past (just as it is doing today, albeit at a very slow pace). No viable wind-based scenario, however, can explain the quick transport of millions of cubic kilometers of material cross ways large fractions of the planets surface, which apparently occurred repeatedly during Marss ahead of time history. Flowing water, though, has routinely moved big amounts of sediment on Earth and could have done so on the rose-cheeked Planet as well.In addition scrutinizing the shape of Martian landforms, scientists have searched for hints of liquid water in the composition of the planets minerals (Bell 2006). One of the reasons why researchers had long believed that Mars never enjoyed an capacious period of warm and wet climate is that much of the surface not cover by wind-borne dust appears to be imperturbable of material that is largely unweathered patriarchal volcanic minerals such as olivine and pyroxene. If water had flowed over the surface for a long time, the argument went, it woul d have chemically altered and weathered the volcanic minerals, creating forms or other oxidized, hydrated phases (minerals that incorporate water molecules or hydroxide ions in their crystal structure).The emerge paradigm is that Mars had an extensive weakly past puddles or ponds or lakes or seas (or all of them) existing for long periods and receptive to what must have been a thicker, warmer atmosphere. During the first billion or so years of Martian history, the inflamed Planet was a much more Earth-like place, likely hospitable to the formation and evolution of life as currently known. The Martian environs began to change, however, as sulfur built up, the irrigate became acidic and the planets geologic activity waned (Bell 2006). Clays gave way to sulfates as the acid rain (of sorts) continue to alter the volcanic rocks and break pour down any carbonates that may have formed earlier. Over time, the atmosphere thinned out perhaps it was lost to space when the planets ma gnetic field shut off, or maybe it was blown off by catastrophic impacts or sequestered somehow in the freshness. Mars eventually became the cold, arid planet recognized today.This new view of Mars is not yet universally accepted, however. cite questions remain unanswered (Bell 2006) How long did the water flow in the Eberswalde delta for decades or millennia? Where are all the sediments that appear to have been wear away from Meridiani Planum and places such as Gale Crater? And were they eroded by water or wind or something else? What is the global abundance of clay minerals on Mars, and were they ever major components of the planets crust? And, most vexing, where are the carbonates that should have formed in the warm, wet, carbon dioxide-rich environment but have not yet been observed anywhere on Mars, not even in the older terrains where clays have been spy? Acidic water could have destroyed the bulk of the carbonates but surely not all of themPerhaps the most authorized qu estion of all is Did water or life ever exist on Mars, and if so, was it able to evolve as the environment changed so dramatically to the present-day climate? (Bell 2006) The answer depends in large part on how long the Earth-like conditions lasted. What can be deduced is that the past decade of discoveries on Mars may be only a small taste of an even more exciting century of robotic and eventually military personnel exploration.ReferencesAustralian Geographic, (2003) brio on Mars. 08161658, Jul-Sep2003, Issue 71Bell, J., (2006) The Red Planets Watery Past. Scientific American, 00368733, Dec2006, Vol. 295, Issue 6Zimmer, C., (2005) Life on Mars? Smithsonian, 00377333, May2005, Vol. 36, Issue 2