Even though space seems very distant for us, and there is hardly anything more far than the stars in the sky which seem like pieces of sand, people have still always been looking for ways to go to them. Even though trips to distant stars are impossible now due to the lack of technology, people were still always trying to establish contacts with other civilizations through the use of communication systems. Due to establishing satellite communication systems, it could be possible to catch distant signals of aliens in other planets who are also searching for communication in the galaxy.
Philip Morrison and Gueseppe Cocconi have once said: “The probability of success is difficult to estimate, but if we never search, the chance of success is zero”. This statement expressed by the founders of SETI could be its slogan, because without searching and applying new methods the way they were doing, SETI would never reach the heights which it has reached. So, what is SETI? SETI stands for Search for Extra-Terrestrial Intelligence. The brief history of SETI can be described through the following dates. In 1957, the 250ft MK1 radio telescope at Jordell bank was built.
Owing to this invention, the scientists have come to the conclusion that from now on it was possible to communicate even across interstellar distances. In the year of 1959 scientists Philip Morrison and Gueseppe Cocconi wrote a paper which was dealing with experiments which could me made in order to listen out to extraterrestrial signals. According to the scientists, the they didn’t know yet where to search for information on the subject and what the frequency of that research had to be, but all the new that that had to keep looking.
So, they started the first SETI experiment which bore the name of Ozma. After the Ozma project, the scientists turned to the new project which was based on the results of the previous one, and had even more sophistication and difficulty. In 1961 SETI became popular, and its first conference took place. At that time, Soviet scientists also got very interested in SETI due to its outstanding results, and thus they started working together with Americans on the future projects. American astronomer Dr. Carl Sagan was working on the project together with the Soviet astronomer Iosif S. Shkolovskii.
After their efficient work together, the scientists published the first book in this field called “Intelligent Life in the Universe”. 1974 became an important year in the activity of SETI because during this year astronomers made an attempt to send a message to other planets. The message was 1,679 bit in size, and it was being transmitted from the observatory which was located under the ground in Puerto Rico. Even though no messages from other planets were received in the result of the experiment, it served as the beginning for further experiments carried out by SETI scientists.
The US Planetary Society was created in 1979 by Carl Sagan, Bruce Murray, and Luois Friedman, and it was from that time on used as an important place of SETI research. At the same time, the University of California of Berkley started a SETI research named: “Search for Extraterrestrial Radio from Nearby Developed Populations”. The work of SETI was continuing at the same level until the early 1980s when the scientist Paul Horowitz put it on the next level. He suggested to build a spectrum analyzer the specific function of which would be to look for SETI transmissions.
All of the spectrums which already existed weren’t of much use in this task because they were restricted to the list of channels which they could get signals from. The technology proposed by Paul Horowitz was of much higher level because owing to it the spectrum could use “autocorrelation” receivers in order to track other channels. After the research on this proposal was carried out, the result was a portable spectrum analyzer which was called “Suitcase SETI”. It could track around 131,000 channels.
By 1983, during the project called “Sentinel”, this spectrum analyzer was finally tested and launched on the Harvard/Smithsonian telescope at Harvard. 1992 was remarkable in the history of SETI because at this time American government for the first time sponsored an operational project carried out by SETI. “Microwave Observing Program” had a long-time effect and was created to search the sky along with “Sky Servey”. The characteristics of the equipment used in the project were very advance: “The signals were to be analyzed by spectrum analyzers, each with capacity of 15 million channels.
These spectrum analyzers could be ganged to obtain greater capacity. Those used in the Targeted Search had a bandwidth of 1 hertz per channel, while those used in the Sky Survey had a bandwidth of 30 hertz per channel” (1). An important SETI establishment SETI@home was founded in May of 1999 and provided its activity until 2001. It was introduced by The University of California, Berkeley. Owing to SETI@home, many people who were interested in the research could download from the Internet the screen saver software.
The program “performed signal analysis on a downloaded 350 kilobyte work unit of SERENDIP IV SETI radio survey data, and then reported the results back over the Internet” (1). Many people who had computers got very interested in the program, and were using it for a long time. After the success of the first SETI@home project, a new one was introduced because the interest towards space in people never goes way.
1. History of SETI- Search for Extra-Terrestrial Intelligence. www. jb. mn. ac 2. History of SETI. www. jb. mn. ac. uk