The Search For Intelligent Life Essay Research

The Search For Intelligent Life Essay, Research Paper

The Search for Intelligent Life

A pioneer in NASA’s Search for Extraterrestrial Intelligence (SETI), Frank Drake, proposed an equation that calculates the number of civilizations in the galaxy. It is based on the fraction of stars with planets, the proportion of those that are inhabitable and the life of technological civilizations (Overbye 46). Optimists, using the equation, have arrived with 1 million civilizations in the milky way alone. Looking at the size of the universe and how common certain compounds are, that number shouldn’t be too far from the truth. With so much of our surroundings we haven’t seen and don’t know of, it shouldn’t be surprising that we are not alone.

Even if we don’t know if extraterrestrials exist, we can hypothesize on what type of planet they could survive on. Water is an essential compound because of its necessity towards life. It provides an area for biochemical reactions, and could exist of planets similar to earth in size and distance from the sun (Angel and Woolf 62). Those planets have a chance of containing carbon based life forms. Carbon is an extremely important compound because it is the foundation of most organisms. Its abundance in the universe and ability to form complex molecules increase the chance of it being the building block of other civilizations (Angel and Woolf 61). Gravity is necessary because it holds the planet together. It must be strong enough to hold the atmosphere and water on the planet’s surface. The size and density of the planet determines the gravity of the body (Angel and Woolf 62).

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Radio waves are a better means of communication because of the possibility of vocally communicating rather than just seeing them with telescopes. The history of radio communications begins in 1969, when the idea was suggested by two physicists, Morrison and Giuseppe Cocconi (Overbye 44). They were chosen because they are a more efficient and economical way to communicate. We have been broadcasting the existence of humanity for 50 years through radio and television signals, and those signals have passed more than 1000 stars (Overbye 44). All these searches are based on the assumption that life can be found within 80 light years of the sun (Henbest). The one problem of using radio waves is finding the frequency and star an extraterrestrial may try to signal from. To aid in that search, two paths have been taken. The first is the multi-channel spectrum analyzer, created by NASA, defeats the problem of trying to find the right frequency. It splits the signal into 74000 frequency channels and searches them all simultaneously (Overbye 48). The other path is the hydrogen atom frequency. Hydrogen atoms emit a radiation when the axis on which the orbiting electrons spin, flips from being parallel to the nucleus to being opposite. SETI scientists believe this frequency would be chosen by other intelligent life. Bob Dixon of Ohio State University, works full-time on searching the frequency hydrogen atoms emit(Henbest). Spectroscopy is a method that uses light coming from the body and analyzes it for any markers that help researchers determine things like temperature, atmospheric pressure, and chemical composition. Out of these markers, radio signals are the easiest to spot (Angel and Woolf 60).What if we do find a signal. Both the International Astronomical Federation (IAC) and NASA have come up with protocols on what to do if a possible E. T. signal is picked up. With the IAC protocol, the signal is verified by computers and operators, then information about it is sent through regular science and public channels (Overbye 48). The NASA protocol minimizes the chance that a false discovery or hoax could pass for a true

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signal. The computer goes through a series of checks and exercises to verify the signal. Then it notifies the operator who monitors the source and takes it from there (Overbye 48).

Probably the most exciting news in the search for life is the mars meteorite that was discovered in the Allan Hills of Antarctica. It was found eight years ago and named ALH84001, after Allan Hills, where it was found (Cowen). It shows evidence that life may have existed on mars 3.6 billion years ago. Apart from containing magnetite and iron sulfide, compounds also produced here on Earth (Cowen). It carried tiny, tubular, egg-shaped structures that looked like fossils of ancient single-celled bacteria also found on Earth (Cowen). Another exciting discovery is the possibility of one of Jupiter’s moons, Europa, containing life. Europa’s atmosphere is rich in oxygen, satisfying the basic characteristics. The Jovian moon is completely enveloped in water, both frozen and solid, but the core may be hot, allowing life to survive and grow in its deep waters (Broad). Fissures were found on the icy surface, suggesting oceanic currents. Plans are being made to take pictures of the moon through Galileo in February (Broad). Also, during an extended mission in 1997 and 1998, pictures will be taken from 400 miles away from the surface Europa (Broad). The discoveries of possible areas of life have excited the world and will carry its interest well into the next century, hopefully enough time for manned visits and maybe even communication.

For many years, people claimed they saw UFOs in the sky, and most of those claims sounded outrageous. But