Scientists from the estimates that only in our galaxy there may be thousands of civilizations, which in principle can be established radio contact. In this case, the average distance between them is thousands of light years. You can not even dream about getting people could visit them with the spacecraft. After all, it would have had to break up cell phones to nearly the speed of light. Although the laws of physics, it is not forbidden, even with the help of fusion engines such flights would require extraordinary expenses.
Much easier, faster and cheaper to install with the "brothers in mind" electromagnetic communication — radio or optical. For example, with modern radars used for radar satellites and planets, can be almost no cost to send the news of another civilization, located thousands of light years away. Search for communication with extraterrestrial civilizations that may exist on planets near other stars, scientists conducted Canada, Russia, the United States and other countries. This search is based on trying to register the radio civilizations may exist in our galaxy.
In the galaxy of about 200 billion stars. It is estimated that about half of them have planetary systems and that an average of two planets in each system, in principle, suitable for the development of life on them. Biochemical Laboratory experiments show that under favorable conditions, a simple substance quickly transferred into an organic form which may lead to the emergence of life. Biological evolution and the struggle for survival in conditions of limited food and energy resources will almost certainly lead to the emergence of intelligent beings and civilization. From these considerations it can be concluded that each year in the galaxy should appear one new technical civilization.
Much more difficult to estimate how long such a civilization will remain at that level of development, which will allow us to register. Now we are able to detect over interstellar distances, the signals of television stations and powerful radars. But it is obvious that such civilizations transmit signals only to a short segment of its history. The development of technology is quickly making unnecessary so wasteful methods of communication.
In less than 100 years after the discovery of radio waves, and the earthly civilization began the transition from radio to a significantly more cost-effective cabling, laser and fiber optic communications. And if we can prevent the possibility of war, and a powerful radar will soon disappear. Thus, the Earth's civilization was "radiogromkoy" less than a century. Of course, our civilization — not an example to others. Still, it can be assumed that in the history of any civilization during its high activity in the radio, when it can be seen at interstellar distances, lasts from 100 to 10 000 years.
Economic estimates show that it is most advantageous to install the interstellar communication at a wavelength of about 10 cm have shorter wavelengths, each electromagnetic quantum-transporting unit of information, has great energy and, therefore, is more expensive. But at longer wavelengths natural radiation of the interstellar medium of the galaxy creates such strong interference that must be overcome for them to significantly increase the transmitted signal power. For this reason, almost all past and current programs for Search for Extraterrestrial Intelligence undertaken by radio telescopes. In the first one carried out in 1960, the National Radio Astronomy Observatory in Green Bank (units Zap. Virginia, USA), tried to take the signals from the nearest stars to the Sun. By the end of 1970 in Green Bank was surveyed about 700 stars in the Galaxy. Similar searches were also conducted at radio observatories Algonquin (Canada), University of pieces. Ohio (USA), and close to Moscow and Nizhny Novgorod. Search for signals from nearby galaxies taken through the world's largest radio telescope at Arecibo on about. Puerto Rico. In 1992, the program has started search for extraterrestrial signals, designed for 10 years. The search is on two levels: a radio antenna with a diameter of 34 m in the Mojave Desert (California) is conducting a systematic survey of the entire sky, the band for band, watching at the same time a multitude of stars and giant antenna diameter of 305 m telescope at Arecibo is trying to fix the signals from individual stars.
If in 1960 — 1970 years of the search carried out on a few waves (21 cm, 18 cm), it is now receiving signals simultaneously in a set of narrow frequency bands, which greatly increases the efficiency of search. Yet under the current radio astronomy techniques have a chance to fix the signals just a very powerful energy-related or
civilizations. To increase the efficiency of the search need much larger radio telescopes sensitive receivers and powerful computers. Such a system — the project "Cyclops" — developed at NASA and could be implemented immediately, but its cost is very high. There have also been attempts to search for signals in the optical and infrared regions of the spectrum, but they have not yet been successful.
In the search for interstellar signals are solved not only the radio problems, but also the most complex information and linguistic problems, such as how to distinguish natural from artificial signal, as the highlight of useful information in it and decipher its meaning, how to compose a message to other sentient beings who do not know about us nothing. It uses the methods of cybernetics, cryptography, and psychology. Carried out and sending interstellar messages of different types. The first of these plaques were aboard space probes "Pioneer 10" and "Pioneer 11", which was launched respectively in 1972 and 1973 and has left the solar system. On these plates shows the position of the Earth in the solar system and the galaxy, as well as a person's appearance. The next radio message was sent from the Arecibo Observatory in November 1974 towards the globular cluster M 13. It contains data about the appearance and human biochemistry, about the population structure of the Earth and the solar system, about the level of our technology. The third message was sent in 1977 on board the interplanetary station "Voyager 2" also has left the solar system. This is a metal disk with a diameter of 30 cm, on which an entry is made on the basis of gramophone record. It recorded natural sounds — the sound of the sea and the forest, animal cries, and greeting people in different languages and fragments of known pieces of music. In addition, the method of television scanning it recorded 118 images with views of the Earth and planets, people and animals, a lot of scientific data.
Humanity has recently received the first signal from outer space, which seems to have extraterrestrial origins. With such an eye opener made by American scientists at the National Astronomy and Ionosphere Center, University of California at Berkeley. Information about this appeared in the beginning of September this year, but this sensational information eclipsed the hostage tragedy in Russia. Signal, called SHGb02 +14 a, was found Arecibo radio telescope in Puerto Rico as part of the international work program on the search for extraterrestrial intelligence with distributed computing SETI @ home. However, it is possible that an unknown signal was caused by unknown natural phenomenon, since similar cases in the history of the hunt for extraterrestrial intelligence have already been. He could also be generated by the telescope Arecibo, which has a fixed dish reflector diameter of 305 m and scans the heavens by changing the position of the receiver relative to the mirror.
The program SETI (Search for Extraterrestrial Intelligence) is based on the assumption that a systematic search in space can detect artificial signals emitted either intentionally or as a random electromagnetic noise, just like the Earth emits a range of TV and radio signals. However, it is not clear how to interpret the information that may bring artificial signals.
Since 1999, the Arecibo radio telescope purposefully searched the vault of heaven in search of messages from extraterrestrials. The obtained data came on home and work computers enthusiasts who have agreed to participate in the project. By 2004, the number had reached 4 million. Day after day, a special program, SETI @ home screensaver analyzes the information received. Scientists are interested in clear and repetitive radio signals emanating from the same point of space. Such signals to date were about two hundred.
Researchers working in the program SETI, assume that signals are directed toward the Earth, at least initially, will likely carry a mathematical, physical and other information of a scientific nature. According to scientists, if the aliens are intelligent enough to build radio telescopes and lasers are powerful enough to mouth-
navlivat interstellar communication, they must be familiar with the same principles of mathematics, physics and chemistry, which are known in the world. But what if extraterrestrial beings will try to report on the more characteristic features of their world — their culture and history?
Anthropologists Ben Finney and Jerry Bentley, University of Hawaii believe that this can help the experience of previous attempts to decipher the languages of ancient civilizations on Earth.
Finney and Bentley reminded often carried analogy between receiving terrestrial civilization meaningful signal from space and re-acquisition of medieval Europe of knowledge accumulated in ancient Greece. There is a very strong likelihood that if humans and receive signals from space that carry some information, they can be a source of long-dead civilization. Newfound heritage of the ancient world Concentrator
lo European civilization a new vision of the world so that in future the European culture was a synthesis of European and ancient Greek philosophy. The same is likely to happen in the case, and if we can get to decipher the message of cosmo-