Example research essay topic: Life On Earth Liquid Water - 1,175 words

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The view of Christiaan Huygens, the Dutch mathematician and physicist who discovered Saturn's moon Titan in 1655, was as follows: Now can anyone look upon, and compare these systems (of Jupiter and Saturn) together, without being amazed at the vast magnitude and noble attendants of these two planets, in respect of this little pitiful Earth of ours? Or can they force themselves to think, that the wise Creator has disposed of all his animals and plants here, has furnished and adorned this spot only, and has left all those worlds bare and destitute of inhabitants or that all those prodigious bodies were made only to twinkle to, and be studied by some few perhaps of us poor fellows? (q. in Sagan, Cosmos 130) Millions of dollars and many brilliant minds have long been dedicated to unlocking the great mysteries of the universe. Perhaps the greatest mystery is whether or not life exists on planets other than Earth. Plato, Epicurus, Isaac Newton, and Benjamin Franklin all shared a belief in extraterrestrial civilization (Search par. 10). Due to newfound understandings of the size and complexity of the universe, the current knowledge of life and its ability to thrive in even the most extreme circumstances, and lack of a reasonably unquestionable skeptical view, the answer to Are We Alone?

is undoubtedly no. The sheer size of the universe presents unlimited possibilities for extraterrestrial life. There are an estimated one hundred billion (100, 000, 000, 000) galaxies in the universe (By the Numbers). The Milky Way galaxy, which houses the solar system that is home to Earth, is some 100, 000 light years across (1 light year is equivalent to 5. 9 trillion miles). It contains approximately four hundred billion (400, 000, 000, 000) stars (Chyba par. 18). Among the factors used to determine how suitable a star is for supporting habitable planets are energy, gravity, and life spans of these stars as relative to time necessary for the evolutionary process to take place (Brownsberger).

There are seven main spectral classifications, including (listed from hottest and largest to coolest and smallest) types O, B, A, F, G, K, and M. Types O and B, which make up less than two percent of the four hundred billion stars in our galaxy, are the only classes believed to be incapable of supporting life (Zubrin 232). Type G stars, the same type as our very own Sun, number around a couple hundred million inside the confines of the Milky Way (Morrison par. 5). In order for life to exist, not only must there be stars, but there must also be planets.

In April of 1999, astronomers announced the first discovery of a solar system other than our own. This solar system consists of three large planets that orbit the star Upsilon Andromeda e, forty-four light years away (Astronomy par. 1). In August of 2000, scientists discovered that the star Epsilon Eridani, which lies a mere 10. 5 light years from Earth, harbors a planet. It could even harbor another solar system (Cowen par. 2). Thanks to new Doppler techniques, the technology of direct orbit wobble viewing, and other methods used by astronomers, there is now evidence of some twenty extra-solar planets. This sample suggests that somewhere between ten and a hundred million solar systems could be found in the Milky Way galaxy around Sun-like stars (Morrison par. 8).

As Carl Sagan so eloquently stated: Despite its 10, 000 -million-mile diameter, the solar system is dwarfed by the Milky Way galaxy to which it belongs. But the Milky Was only a mote in the universe. There are thousands of millions of such galaxies, most with their own myriad stars having their own planetary systems. If only 1 / 10, 000 of 1 percent of these planets harbor a civilization and this is a very conservative estimate the universe must teem with more than 100 million million civilizations. (Planets par. 21) It has already been proven, by scientific experiments involving Mars Jars, that many earthly micro-organisms are capable of surviving under Martian conditions, including extreme cold, dryness, and variance in atmospheric pressure and composition (par. 9).

Here on Earth, life is known to flourish in the most extreme environments, including lava-spewing volcanoes, nuclear reactor cores, and layers of subzero arctic ice (Origins: Astrobiology par. 2). Life on Earth is well-adapted because this is where it has always been. Naturally, life forms originating on another planet would be well-adapted to that planet as well (Sagan, Cosmos 14). Is it not reasonable to assume that life originating elsewhere in the universe would be no less adaptable to extreme heat, cold, and even radioactivity than life on Earth? Many believe liquid water and oxygen to be necessary factors in the existence of life. But if terrestrial organisms exist that are capable of thriving without free oxygen, why wouldnt extraterrestrial organisms be capable of this same feat?

This, of course, is assuming that they dont require some other form of gas for respiration. The same can reasonably be said for liquid water. Perhaps alien life forms are capable of retaining a water supply in their tissues and acquiring alternate forms of water from the environment (Sagan, Planets par. 9). Thus far, scientists are only able to study and compare life on Earth. This gives them a very limited knowledge when viewing life on a cosmic level (Sagan, Cosmos 4).

Many scientists harbor a belief in subsurface life forms, which may inhabit places such as Mars and the moons of Jupiter. It is already known that there is a subsurface biosphere on Earth that possibly equals or even exceeds the mass of all organisms on Earths surface. This certainly supports the possibility of subsurface life on Mars or Jupiter's moons (Chyba par. 5). The Galileo spacecraft has shown evidence for oceans beneath the ice surfaces of the Jupiter moons Europa, Callisto, and Ganymede. Since liquid water is necessary for life on Earth, proof of liquid water on these moons greatly increases the chance of extraterrestrial life in our solar system (Name). Terrestrial life is based on organic molecules, which are now known to be plentiful throughout space (Chyba par. 2).

Radio emission lines shown by gas clouds prove this presence of carbon compounds (Morrison par. 9). And though the presence of these molecules and compounds certainly does not prove that life exists in outer space, it is definitely a foundation for it. Biophysicist Stuart Kauffman believes that life is an unavoidable result of chemistry (Search par. 31). The chemistry is undoubtedly there. Though the argument for the possibility of alien life forms throughout the universe is quite strong, there are still many opponents.

The most often used reasoning by these skeptics is known as the Fermi Paradox, which asks the seemingly simple question, Where are they? Physicist Enrico Fermi proposed that in the suspected 12 - 15 billion-year age of the universe, sentient alien life forms have had more than ample time to spread throughout the galaxy, colonizing habitable planets. This would naturally include Earth (Shostak). There are ma...

Research essay sample on Life On Earth Liquid Water