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Name: Nicole M.
ProgramYear: 2006 Submit Date: May 30, 2006 Review Date: Jun 12, 2006 
Ad astra per scientiam. Amidst the vast and elegant ocean of spacetime, stars, more innumerable than the sand grains comprising every shore of Earth, sail, fading and dawning according to the caprice of their fiery hearts. Consequently, it would be almost presumptuous to assume that only Earth--a comparatively tiny planet in the outskirts of an unspeakably vast and enigmatic universe-- sustains life. The advent of space exploration has culminated in the discovery of a brother, if not a fraternal twin, whose similarities present a prospect for life on foreign territory yet whose divergences are quite indicative of the fate that awaits our own precious planet.
According to estimation and theory, Earth, alongside its solar system brethren, was born approximately 4.55 billion years ago from the dust and debris of a solar nebula, ultimately sustaining its molten-hot exterior for the first 0.8 billion years of its existence due to intense bombardment from the rubble of the developing solar system. As bombardment abated, the surface cooled and formed a solid crust, through which outgassing and volcanic activity produced the primordial atmosphere and seemingly intolerable conditions that microscopic life triumphantly arose from. Though the exact composition of Earth’s early atmosphere is a subject of considerable debate, one prevalent theory assumes that Earth had a reducing atmosphere consisting principally of carbon dioxide, nitrogen gas, and water vapor as well as hydrogen gas and other hydrogen compounds. Whereas the ampleness of hydrogen in such an atmosphere would reduce the amount of energy necessary to form the carbon-rich organic molecules, the miniscule amounts of oxygen would prevent the spontaneous reactions between amino acids and oxygen that would prevent amino acids from surviving long enough to constitute proteins. That is, such an atmosphere would be inherently conducive--though not necessarily favorable--to the formation of life. The existence and composition of a primordial Martian atmosphere and climate, however, remains a mystery whose answer lies in well-preserved geological evidence. The surface of Mars, like its Earthen brother, was carved and chiseled (as presumed by some geochemists) from tectonic activity, volcanism (which would have injected gases, such as carbon dioxide, sulfur dioxide, and water vapor that can culminate in a greenhouse effect), and intense erosion from ice, wind, and perhaps most intriguingly of all, liquid water. The discovery of physical features resembling gorges and shorelines, compounded by the detection of minerals, such as hematite and goethite that only form in the presence of water strongly suggests a previous abundance of water above the surface. The discovery of large dry valleys featuring streamlined walls, scoured floors, and tear-shaped islands furthermore indicate massive floods, some surpassing one hundred times the annual outflow of the Mississippi River. Whereas these valleys are primarily located around the Chryse basin, they occur in several other Martian regions and vary considerably in age, according to the impact craters superimposed on them. Branching valley networks characterized by tributaries and apparent increases in size downstream likewise exist all throughout the cratered terrain, indicating running water as the erosive agent. Despite substantial geological evidence for the presence of liquid surface in Mars’s tumultuous past, however, water could presently exist on Mars only under transitory, metastable conditions, due to the extremely thin atmosphere. Whereas Earth has approximately 101.3 kPa of pressure at its surface, the Martian atmosphere comprises only 0.7 to 0.9 kPa of pressure, resulting in its inability to store heat and consequent subfreezing temperatures. Even if the temperature were above freezing, however, the thinness of the atmosphere forbids the presence of liquid water, causing all melted ice to evaporate instantly . Such conditions, when contrasted to the extensive degradation attributed to running water that occurred until approximately 3.5 Gyr ago, suggest that the Martian climate and atmosphere have evolved drastically, though it is difficult to ascertain the difference. One indication resides in the theoretical possibility of plate tectonics, which not only helps bridge the gap between Earth and Mars and poses another reason for fundamental climatic changes, but also suggests the existence of water, the fundamental requisition for life. Whereas Mars no longer sustains a magnetic field, the discovery of Earth-like magnetic field stripes--as opposed to randomly-oriented magnetic patches--by Mars Global Surveyor indicates not only the presence of an earlier magnetosphere memorialized in Martian crustal rocks, but also the prospect of plate tectonics. The positive and negative field stripes discovered along Earth’s Mid-Atlantic Ridge culminate from the forced separation of plates as molten rock seeps through. As the plates spread and cool, they become magnetized according to the direction of Earth’s global field, which changes several times over the course of a million years. The discovery of such patterns on Mars alludes to, though fails to offer any conclusive evidence of, the prospect of tectonic plates, which would subsequently allude to the existence of water--a requisite lubricant for Earth’s tectonic plates--in Mars’s interior. Earth moreover maintains a magnetosphere that is attributed to the charged currents in its molten interior, as opposed to its metal core, since metals lose magnetism at sufficiently high temperatures. The similar rates of rotation (a contributing factor to the strength of a planet’s magnetosphere) and interior composition between Mars and Earth render the lack of a Martian magnetosphere an enigma, at first glance. However, its answer is the same for Mars’s lack of atmosphere, frigid temperatures, absence of tectonic shifting, and geological preservation: whereas Mars resembled Earth in its embryonic stages, its smaller size provided less internal friction and radioactive decay, causing it to cool and meet its geological death much more rapidly. However, it is not unique in this respect; for Earth, though presently driven by its internal heat and molten core to smash and push away its continents, will eventually cool, quieting its magnetic field and ultimately succumbing to the sun, which will likewise steal its atmosphere and absorb its precious, life-sustaining water.
If Earth is intended to follow a path similar to Mars’s, however, does that mean that Mars once had--or perhaps still has--the Earthen capacity for life? Whereas similarities in atmospheric circulation patterns, seasonal color changes, rotational rates, and axial tilt between Earth and Mars render the latter a likely candidate for life, many mission biologists consider its surface absorption of extensive--and virtually unhindered--solar ultraviolet radiation, extreme aridness, and oxidizing soil chemistry to be sterilizing. Moreover, whereas Earth’s single, large moon stabilizes its axial tilt through tidal interaction, the small sizes of Phobos and Deimos--the two moons orbiting Mars--fails to provide the same effect, resulting in a “chaotically unstable” rotational axis subject to the gravitational torque of the Sun and planets. Many theorists believe that the severe weather oscillations and seasonal differences would prevent flora and fauna from surviving long, though nothing is conclusive. However, research conducted with the Andromeda Chamber, which simulated Martian atmospheric conditions, indicates that microbial methanogens (which produce methane as a by-product) are capable of living in the lower Martian atmospheric pressure and in Martian soil. Traces of methane in the Martian atmosphere offer a tantalizing possibility for undiscovered microbial life, though the methane is likely a product of other natural processes. Regardless, the intense ultraviolet radiation bombarding Mars prevents even methanogens--which are among Earth’s most primitive and enduring organisms--from living on its surface. On the other hand, the ever-resilient cyanobacteria (which convert carbon dioxide--the most abundant Martian atmospheric gas--into oxygen and are largely responsible for the evolution of Earth’s atmospheric conditions) produce dormant spores capable of surviving Martian conditions--even its ultraviolet radiation--if shielded by one millimeter of soil and provided with the necessary nutrients. Thus, life is theoretically capable of surviving on Mars, though additional factors may hinder such from actually occurring. The more important question, perhaps, is not whether life can survive on Mars, but rather the impact that microbes cultivated on Mars will have on Earth organisms with absolutely no immunity, though that may be discovered in the relatively near future.
Overall, the relationship between Mars and Earth remains a rather enigmatic one; though certain similarities are undeniable, the differences may be sufficient to prevent life--whether Earth-born or Martian--from ever bridging the gap. The composition of the Martian atmosphere--95% carbon dioxide, 3% nitrogen, trace amounts of water vapor, and apparently no oxygen--presents an interesting parallelism between present Mars and primitive Earth that may proffer the answer to the questions concerning the latter’s atmospheric and biological evolution. Ultimately, the theory of a reducing atmosphere culminating in life on Earth is flawed by the very elements it proposes; although it stands on a verifiable premise, much of that premise is also a product of man’s imagination: that is, what could produce life, as opposed to what did produce life, as was the famous experiment simulated by Miller and Urey. The theory’s presumption that oxygen was absent allows the atmosphere to be conducive to the formation of proteins, but falls when the lack of ozone--which is essential to protecting the delicate proteins from ultraviolet radiation--is taken into account. If microbial life is capable of surviving on Mars--which is very similar in many respects to primitive Earth, absence of oxygen included--the resulting data may illuminate the flaws in this theory so that they may be amended or otherwise result in the discarding or vindication of this theory as an entity. Ultimately, the evolution of life in the universe may be dependent on the conditions that require the lowest energy for life to form, or perhaps rely primarily on which chemicals produce the necessary reactions, or a certain combination of both. Either way, Mars becomes favorable in this respect, because its fundamental elements, though seemingly intolerable, are theoretically conducive to life, and thus hold the key to multifarious aspects of Earth’s past, present, and future. If life is successfully discovered or implanted on Mars, it will inevitably be different. Microgravity in space, for instance, causes considerable changes in physiological functioning of large organisms, but can also cause microbes, such as E. coli, to become more virulent. The considerable disparity in gravitational acceleration between Earth and Mars will likewise entail variations in microevolution and fundamental functioning that may prohibit or perfect life. Tempus solum dicere potest.
Amidst the vastness of space, we stand as our forefathers once did, of little consequence to the universe though insatiable in our curiosity of it. Our exploration of Mars is a tiny step towards reaching an ultimately unattainable goal; after all, how can we understand the fundamental nature of the enigmatic and elegant universe, if we ourselves live within it? How can a part contemplate and fully comprehend the system? Overall, everything we know is inherently circumstantial, and thus we will never come to an absolutely conclusive conclusion. But of course, how many times before have we achieved the impossible?
“Researchers: Mars once hummed with magnetism, like Earth.” 29 April 1999. 25 May 2006
Name: Nicole M.
ProgramYear: 2006 Submit Date: May 30, 2006 Review Date: Jun 12, 2006 
Ad astra per scientiam. Amidst the vast and elegant ocean of spacetime, stars, more innumerable than the sand grains comprising every shore of Earth, sail, fading and dawning according to the caprice of their fiery hearts. Consequently, it would be almost presumptuous to assume that only Earth--a comparatively tiny planet in the outskirts of an unspeakably vast and enigmatic universe-- sustains life. The advent of space exploration has culminated in the discovery of a brother, if not a fraternal twin, whose similarities present a prospect for life on foreign territory yet whose divergences are quite indicative of the fate that awaits our own precious planet.
According to estimation and theory, Earth, alongside its solar system brethren, was born approximately 4.55 billion years ago from the dust and debris of a solar nebula, ultimately sustaining its molten-hot exterior for the first 0.8 billion years of its existence due to intense bombardment from the rubble of the developing solar system. As bombardment abated, the surface cooled and formed a solid crust, through which outgassing and volcanic activity produced the primordial atmosphere and seemingly intolerable conditions that microscopic life triumphantly arose from. Though the exact composition of Earth’s early atmosphere is a subject of considerable debate, one prevalent theory assumes that Earth had a reducing atmosphere consisting principally of carbon dioxide, nitrogen gas, and water vapor as well as hydrogen gas and other hydrogen compounds. Whereas the ampleness of hydrogen in such an atmosphere would reduce the amount of energy necessary to form the carbon-rich organic molecules, the miniscule amounts of oxygen would prevent the spontaneous reactions between amino acids and oxygen that would prevent amino acids from surviving long enough to constitute proteins. That is, such an atmosphere would be inherently conducive--though not necessarily favorable--to the formation of life. The existence and composition of a primordial Martian atmosphere and climate, however, remains a mystery whose answer lies in well-preserved geological evidence. The surface of Mars, like its Earthen brother, was carved and chiseled (as presumed by some geochemists) from tectonic activity, volcanism (which would have injected gases, such as carbon dioxide, sulfur dioxide, and water vapor that can culminate in a greenhouse effect), and intense erosion from ice, wind, and perhaps most intriguingly of all, liquid water. The discovery of physical features resembling gorges and shorelines, compounded by the detection of minerals, such as hematite and goethite that only form in the presence of water strongly suggests a previous abundance of water above the surface. The discovery of large dry valleys featuring streamlined walls, scoured floors, and tear-shaped islands furthermore indicate massive floods, some surpassing one hundred times the annual outflow of the Mississippi River. Whereas these valleys are primarily located around the Chryse basin, they occur in several other Martian regions and vary considerably in age, according to the impact craters superimposed on them. Branching valley networks characterized by tributaries and apparent increases in size downstream likewise exist all throughout the cratered terrain, indicating running water as the erosive agent. Despite substantial geological evidence for the presence of liquid surface in Mars’s tumultuous past, however, water could presently exist on Mars only under transitory, metastable conditions, due to the extremely thin atmosphere. Whereas Earth has approximately 101.3 kPa of pressure at its surface, the Martian atmosphere comprises only 0.7 to 0.9 kPa of pressure, resulting in its inability to store heat and consequent subfreezing temperatures. Even if the temperature were above freezing, however, the thinness of the atmosphere forbids the presence of liquid water, causing all melted ice to evaporate instantly . Such conditions, when contrasted to the extensive degradation attributed to running water that occurred until approximately 3.5 Gyr ago, suggest that the Martian climate and atmosphere have evolved drastically, though it is difficult to ascertain the difference. One indication resides in the theoretical possibility of plate tectonics, which not only helps bridge the gap between Earth and Mars and poses another reason for fundamental climatic changes, but also suggests the existence of water, the fundamental requisition for life. Whereas Mars no longer sustains a magnetic field, the discovery of Earth-like magnetic field stripes--as opposed to randomly-oriented magnetic patches--by Mars Global Surveyor indicates not only the presence of an earlier magnetosphere memorialized in Martian crustal rocks, but also the prospect of plate tectonics. The positive and negative field stripes discovered along Earth’s Mid-Atlantic Ridge culminate from the forced separation of plates as molten rock seeps through. As the plates spread and cool, they become magnetized according to the direction of Earth’s global field, which changes several times over the course of a million years. The discovery of such patterns on Mars alludes to, though fails to offer any conclusive evidence of, the prospect of tectonic plates, which would subsequently allude to the existence of water--a requisite lubricant for Earth’s tectonic plates--in Mars’s interior. Earth moreover maintains a magnetosphere that is attributed to the charged currents in its molten interior, as opposed to its metal core, since metals lose magnetism at sufficiently high temperatures. The similar rates of rotation (a contributing factor to the strength of a planet’s magnetosphere) and interior composition between Mars and Earth render the lack of a Martian magnetosphere an enigma, at first glance. However, its answer is the same for Mars’s lack of atmosphere, frigid temperatures, absence of tectonic shifting, and geological preservation: whereas Mars resembled Earth in its embryonic stages, its smaller size provided less internal friction and radioactive decay, causing it to cool and meet its geological death much more rapidly. However, it is not unique in this respect; for Earth, though presently driven by its internal heat and molten core to smash and push away its continents, will eventually cool, quieting its magnetic field and ultimately succumbing to the sun, which will likewise steal its atmosphere and absorb its precious, life-sustaining water.
If Earth is intended to follow a path similar to Mars’s, however, does that mean that Mars once had--or perhaps still has--the Earthen capacity for life? Whereas similarities in atmospheric circulation patterns, seasonal color changes, rotational rates, and axial tilt between Earth and Mars render the latter a likely candidate for life, many mission biologists consider its surface absorption of extensive--and virtually unhindered--solar ultraviolet radiation, extreme aridness, and oxidizing soil chemistry to be sterilizing. Moreover, whereas Earth’s single, large moon stabilizes its axial tilt through tidal interaction, the small sizes of Phobos and Deimos--the two moons orbiting Mars--fails to provide the same effect, resulting in a “chaotically unstable” rotational axis subject to the gravitational torque of the Sun and planets. Many theorists believe that the severe weather oscillations and seasonal differences would prevent flora and fauna from surviving long, though nothing is conclusive. However, research conducted with the Andromeda Chamber, which simulated Martian atmospheric conditions, indicates that microbial methanogens (which produce methane as a by-product) are capable of living in the lower Martian atmospheric pressure and in Martian soil. Traces of methane in the Martian atmosphere offer a tantalizing possibility for undiscovered microbial life, though the methane is likely a product of other natural processes. Regardless, the intense ultraviolet radiation bombarding Mars prevents even methanogens--which are among Earth’s most primitive and enduring organisms--from living on its surface. On the other hand, the ever-resilient cyanobacteria (which convert carbon dioxide--the most abundant Martian atmospheric gas--into oxygen and are largely responsible for the evolution of Earth’s atmospheric conditions) produce dormant spores capable of surviving Martian conditions--even its ultraviolet radiation--if shielded by one millimeter of soil and provided with the necessary nutrients. Thus, life is theoretically capable of surviving on Mars, though additional factors may hinder such from actually occurring. The more important question, perhaps, is not whether life can survive on Mars, but rather the impact that microbes cultivated on Mars will have on Earth organisms with absolutely no immunity, though that may be discovered in the relatively near future.
Overall, the relationship between Mars and Earth remains a rather enigmatic one; though certain similarities are undeniable, the differences may be sufficient to prevent life--whether Earth-born or Martian--from ever bridging the gap. The composition of the Martian atmosphere--95% carbon dioxide, 3% nitrogen, trace amounts of water vapor, and apparently no oxygen--presents an interesting parallelism between present Mars and primitive Earth that may proffer the answer to the questions concerning the latter’s atmospheric and biological evolution. Ultimately, the theory of a reducing atmosphere culminating in life on Earth is flawed by the very elements it proposes; although it stands on a verifiable premise, much of that premise is also a product of man’s imagination: that is, what could produce life, as opposed to what did produce life, as was the famous experiment simulated by Miller and Urey. The theory’s presumption that oxygen was absent allows the atmosphere to be conducive to the formation of proteins, but falls when the lack of ozone--which is essential to protecting the delicate proteins from ultraviolet radiation--is taken into account. If microbial life is capable of surviving on Mars--which is very similar in many respects to primitive Earth, absence of oxygen included--the resulting data may illuminate the flaws in this theory so that they may be amended or otherwise result in the discarding or vindication of this theory as an entity. Ultimately, the evolution of life in the universe may be dependent on the conditions that require the lowest energy for life to form, or perhaps rely primarily on which chemicals produce the necessary reactions, or a certain combination of both. Either way, Mars becomes favorable in this respect, because its fundamental elements, though seemingly intolerable, are theoretically conducive to life, and thus hold the key to multifarious aspects of Earth’s past, present, and future. If life is successfully discovered or implanted on Mars, it will inevitably be different. Microgravity in space, for instance, causes considerable changes in physiological functioning of large organisms, but can also cause microbes, such as E. coli, to become more virulent. The considerable disparity in gravitational acceleration between Earth and Mars will likewise entail variations in microevolution and fundamental functioning that may prohibit or perfect life. Tempus solum dicere potest.
Amidst the vastness of space, we stand as our forefathers once did, of little consequence to the universe though insatiable in our curiosity of it. Our exploration of Mars is a tiny step towards reaching an ultimately unattainable goal; after all, how can we understand the fundamental nature of the enigmatic and elegant universe, if we ourselves live within it? How can a part contemplate and fully comprehend the system? Overall, everything we know is inherently circumstantial, and thus we will never come to an absolutely conclusive conclusion. But of course, how many times before have we achieved the impossible?
“Researchers: Mars once hummed with magnetism, like Earth.” 29 April 1999. 25 May 2006
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