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Space Topics: Search for Extraterrestrial IntelligenceSETI FactsWhat is SETI? SETI is the acronym for the search for extraterrestrial intelligence. It is the search for electromagnetic signals from other civilizations in the universe. Several SETI projects currently operate at different observatories. The majority of SETI efforts search for radio transmissions, but a growing number of programs search for light signals. Who is doing SETI? SETI projects are springing up around the world these days, run by both professionals and amateurs. Two organizations in particular have taken the lead in sponsoring SETI research: The SETI Institute and The Planetary Society. The chief operation of The SETI Institute is Project Phoenix, a highly sensitive search targeting sun like stars, using the Arecibo Radio Telescope in Puerto Rico. Over the years The Planetary Society has sponsored a variety of different projects using different techniques, with a general preference for all-sky surveys. Here are a few highlights of projects Planetary Society Members have supported: SETI@home: Millions of users around the world processing radio data collected by the Arecibo radio telescope in Puerto Rico on their own personal computers. Based in Berkeley, California.
Optical SETI: Four projects searching for optical signals from alien civilizations. Two are based in Harvard and two in Berkeley. Project BETA: Harvard's Billion-Channel Extraterrestrial Assay is an all-sky survey using an 84-foot radio telescope at the Oak Ridge Observatory in Massachusetts. Project SERENDIP: The Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations, based in Berkeley, California. Collects and analyses data from a receiver permanently perched on the Arecibo radio telescope in Puerto Rico. Project META II: The Megachannel Extraterrestrial Assay (META II) outside Buenos Aires, Argentina, surveys the Southern skies for an intelligent signal. Why conduct SETI? The detection of another civilization would be one of the most important discoveries in human history. It will permanently change humanity's view of its place in the universe, making it just one member of a universal community of intelligent species. Even the mere knowledge that we are not alone in the universe will transform our understanding of the history and evolution of our species and our planet. Some hope that the mere knowledge that we are not alone in the universe will increase human solidarity by making seemingly insoluble disputes seem trivial when measured against all that humanity holds in common. If we actually manage to communicate with an extraterrestrial civilization, the benefits could be immeasurable: An advanced alien civilization may have solved many of the problems that face us now, such as war, disease, poverty, and environmental destruction. We could learn from their experience. What kind of signals should we look for? Most scientists who have studied the problem believe that radio signals are the most viable way to communicate across the enormous distances that separate the stars. Radio signals travel at the speed of light, and pass through most of our Milky Way galaxy with very little interference. They even pass through thick clouds of dust that prevent us from seeing many stars. Other researchers believe that light waves are at least as likely to be used to communicate between worlds. As a result, in recent years a growing number of Optical SETI ventures are looking for amplified laser signals from the stars. Wouldn't an extraterrestrial civilization use something far more advanced than radio with which to communicate? It's entirely possible that there is some unknown method of communicating, and that radio may seem as primitive to aliens as smoke signals do to us today. However, we can only use the technology we know. Even if a more advanced method of intergalactic communication exists, an extraterrestrial civilization might choose to use radio because it is the most primitive method able to communicate across the galaxy, perhaps increasing their chances of contacting other civilizations. Is there any evidence for life on other worlds? As of yet, there is no convincing evidence that life as we know it (microbial or technologically advanced) exists anywhere other than on Earth. Nor have radio signals ever been detected from planets around other stars. There is, however, an increasing body of evidence that suggests that life may be prevalent in the universe. Recent studies show that life on Earth originated some 4 billion years ago, almost immediately after conditions became tolerable for life. This seems to suggest that life could originate on other planets just as easily. In our own Solar System, Mars and Jupiter's moon Europa may have had the conditions required for the development of life at some point in their history. The discovery in the past few years of planets orbiting distant stars adds weight to this view. Because extrasolar planets are detected by their mass, all the ones found so far are much larger than the Earth. Nevertheless, the discovery of so many of them suggests that detection of Earth-sized planets may not be far behind. If Earth-like planets are indeed prevalent in the galaxy, it seems likely that life as we know it is could exist in them as well. How could we possibly understand signals from another civilization? Even though an alien civilization and we would not have a language in common, there are ways to communicate that should be understandable to intelligent beings. Mathematics, physics, chemistry, and astronomy contain fundamental laws that provide a common "language" throughout the universe. Television pictures are a way of communicating that does not even require a common language to understand. Is NASA conducting SETI searches? Not any more. On September 22, 1993, Nevada Senator Richard Bryan introduced an amendment to the fiscal year 1994 appropriations bill for NASA. The amendment proposed eliminating funding for NASA's SETI program, the High Resolution Microwave Survey (HRMS). Although NASA had been conducting SETI studies since the early 70's, the actual search had been operational for less than a year at the time. Nevertheless the amendment passed, and NASA's SETI effort ended. Much of the HRMS equipment then passed into the hands of The SETI Institute, and was used as the basis for Project Phoenix. Is the government hiding proof of a Martian civilization discovered by the Mars orbiters? This is one of the most absurd claims made by conspiracy buffs. NASA has a great deal of trouble convincing Congress to give it money for planetary research. If NASA had proof of alien artifacts on Mars, they would eagerly show it to all the TV networks, because then the agency would never have any more trouble getting funding from Congress. Wouldn't the government cover up any detection of extraterrestrials? Even if the government wanted to cover up the detection of extraterrestrial life, it wouldn't be able to do so. The scientific searches, both for intelligent and microbial life are being carried out by scientists around the world. The methods that scientists use to confirm their analyses and observations require that the information be distributed to other scientists, making a cover-up extremely difficult. Of course, this also begs the question of what the government would gain by covering up extraterrestrial life. What do I study if I want to go into SETI? The short answer is math, science, and engineering. SETI is unusual because it brings so many sciences together. SETI researchers include astronomers, physicists, electrical engineers, biologists and others. Mathematics is the basis of most sciences and engineering, so the more math you learn, the better. Courses in astronomy, physics, chemistry, biology, and basic electronics are extremely useful for any SETI scientist. Computers are essential to virtually all research, so the ability to program computers will help greatly no matter what you do. If SETI were successful, some knowledge of linguistics would also be of great value, especially if you have learned how very different human languages (such as English, Chinese, and ancient Egyptian) have handled the problems of communication. What is SETI@Home? SETI@home is a project that allows millions around the world to participate in the search for extraterrestrial life. By distributing a free screensaver, SETI@home uses the computing power of millions of personal computers worldwide to process data collected at the Arecibo radio telescope in Puerto Rico. Let personal computer users participate in processing data that might come from an extraterrestrial source. Click here to become a SETI@home user. Why do SETI if UFOs are already here? Although UFOs have been seen for decades, there is no convincing evidence that they represent visits by extraterrestrial beings. Despite all the stories of alien abductions, alien autopsies, and the events at Roswell, no physical evidence has ever been shown to indicate we are truly being visited. On the other hand, the search for evidence of extraterrestrial intelligence is a scientific approach to understand what is in the world around us. SETI really has no connection to UFOs. What's the truth about the Roswell incident? The "truth" about Roswell depends on who you ask. Proponents of UFOs and alien abductions will tell you that an alien spacecraft crashed at Roswell in 1947. However, there is no relevant physical evidence to support this. The only evidence that this happened is the fact that the government denies that it happened! The best determination of the actual events seems to be that a weather balloon crashed near Roswell. Diaries kept by the team of scientists doing balloon experiments in 1947 support this view, and all of the physical evidence that was described in reports at the time can be explained as coming from the balloons that were being used at the time. This view is described in an excellent recent book, entitled UFO Crash at Roswell--Genesis of a Modern Myth, by B. Saler and others. Many thanks to Tom McDonough, SETI Coordinator for the Planetary Society, and Bruce Jakowsky, Professor of Geology and member of the Laboratory for Atmospheric and Space Physics at the University of Colorado, for their input. |
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