This was stated by David Messerschmitt of the University of California at Berkeley. He revealed this statement in his work, which should change the approach to the search for extraterrestrial civilizations.

The most common claim that radio is the best and final form of communication is not the ultimate truth, and this is not surprising, since we ourselves use this technology quite recently (even by earthly standards). However, having no more convenient alternative for searching for other civilizations, this process needs to be optimized and improved as much as possible, Messerschmitt believes.

According to the researcher, the first step is to get rid of the problem of excessive load in the case of listening and sending a signal not to any particular zone, but in all directions. In his opinion, the best optimization strategy should adhere to the principle that the transmission power should be strictly limited. Since the transfer itself takes a huge amount of time, there is no point in chasing a high transfer rate.

There are other options, but each of them has its drawbacks. For example, for economical signal transmission, you can use the polarization of electromagnetic waves and different kinds multiplexing, however, despite the fact that this will save energy, another problem arises - orientation towards contact with civilizations that have already mastered this technology (so, if, the level of technology of an extraterrestrial civilization will be the same as we had in the 1960s years, they will not be able to receive the signal). On the other hand, this minus cannot be called big, but unpleasant - calmly. Therefore, optimization in this vector is rather doubtful.

The researcher suggests using methods that are not popular for SETI. Messerschmitt notes that by using the widest possible range, the average power consumption should be much more economical than the fixed frequency approach (as SETI does). That is, if CCs think the same way, then it is necessary to search for more broadband signals with less power and information transfer rate.

In addition, the author of the paper believes that the SETI approach to search strategy is fundamentally wrong. The main problem lies in the fact that the so-called "truth check" takes a lot of energy for a long repeating signal - they try to distinguish a real signal from a false one by long "listening" to a specific sector. At one time, a similar problem was encountered in 1977, when the so-called “Wow!” signal was registered. This signal was received by the Big Ear radio telescope, but it was the “truth check” method that was used to verify its origin, and the signal was not confirmed and intercepted again. It would seem that listening should go on an ongoing basis, but neither then nor now, such a strategy is not used.

If we follow the thought of David Messerschmitt and assume that the computer transmitting the signal saved energy, then register the signal “Wow!” researchers would not have been able to for a very simple reason - there was no need to repeat the signal more often than, for example, once every few years.

According to the researcher, it is quite simple to avoid such failures - for this you need to systematically and for a long time examine each sector of the sky, moving away from the strategy of non-systematic "listening" different parts and maintain a database of all signals suspected to be artificial.

Note that SETI (Search for Extraterrestrial Intelligence) is the common name for projects and activities to search for extraterrestrial civilizations and possibly make contact with them. The beginning of the project dates back to 1959. There is an opinion that the SETI project can carry a serious danger. It is assumed that a highly developed alien civilization can use radio signals as an information weapon or a means of its own distribution.

In 1960 Cornell University astronomer Frank Drake laid the foundation for an experiment called SETI (Search for Extra-Terrestrial Intelligence), in which scientists around the world are looking for signals from extraterrestrial civilizations. Initially, Drake began to monitor the radio signals coming from the stars Tau Ceti and Epsilon Eridani, which were considered the most likely candidates for the presence of Earth-like planets. Within two months, the antennas were set in the direction of two neighboring stars, his receiver was tuned to a frequency of 1420 MHz. So far, no signals of extraterrestrial origin have been detected. Drake also created his famous Drake Equation formula for calculating the number of civilizations in the galaxy that could be contacted.

Around the same time, the physicists Cocconi and Morrison published an article in the journal Nature, where they noted the great potential in using radio waves in the search for extraterrestrial civilizations.

Physicist Enrico Fermi formulated the thesis (Fermi paradox) in response to a rather high estimate of the chances of interplanetary contact according to the Drake equation: if there are so many alien civilizations, why does humanity not observe any traces of these civilizations? The hypothesis of the uniqueness of the Earth, which is put forward by some physicists and astronomers, is trying to explain this paradox. They argue that all forms of life should be built on carbon, like ours.

Currently, Frank Drake is director of the Center for the Study of Life in the Universe and is engaged in the search for optical signals of extraterrestrial origin, as well as the development of projects for radio telescopes for SETI. In particular, his proposals are used in the design of the Allen Composite Radio Telescope (named after Paul Allen, founder of Microsoft) in California, one of the most famous projects to search for extraterrestrial intelligence.

The first 42 antennas of the telescope were launched in 2007, and in total it is planned to build an array of 350 antennas to search for extraterrestrial civilizations.

In the USSR in the early 1960s, they also showed interest in the search for extraterrestrial intelligent life forms. A group of enthusiasts was assembled at the Sternberg State Astronomical Institute to search for signals from space. This idea was supported by prominent physicists. At that time, the Americans did not enter the name of their SETI project, so the Russian program had an interesting name "Project Au". Russian specialists managed to do a lot during this time: in addition to an active discussion of the problem, distant space depths were mastered. And today, technology allows you to view the Universe in the entire range of radio emissions, taking the emission spectra of distant stars.

In 1962, the first radio message was sent into space, it contained the three words "Peace, Lenin, USSR." In 1774, the Americans sent their signal from a radio telescope to Arecibo. Three subsequent messages were sent from the radar telescope in Evpatoria in 1999, 2001 and 2003 by the Institute of Radio Engineering and Electronics. They contained digital and analog information (texts and music) and headed towards several solar-type stars.

These messages will get, by assumption, at least 30 years and the same amount of time to go back. Some experts believe that all this is an attempt to find a civilization similar to ours. But perhaps there are other civilizations older than ours by millions of years and they communicate with each other with the help of "dark matter". There is an assumption that the presence of this matter explains the "silence" of the Universe. The Physics Institute of the Academy of Sciences has compiled a list of one hundred star systems closest to the Earth, having analyzed the full array of stars discovered by mankind. Of these, approximately 58 may be SETI objects.

In 2006, the US Planetary Society, as part of the SETI project, introduced a new powerful telescope to search for extraterrestrial civilizations. By this time, many years of experience in the field of radio research had been accumulated, and it was decided to direct efforts to search for and fix light, rather than radio signals from space. Visible light can easily move through outer space, and a focused bright beam like a laser can be several times brighter than the Sun, which makes it possible to fix it from cosmic distances. Light signals, unlike radio waves, are unidirectional, which makes it possible to set their source. Extraterrestrial civilizations, according to the American community, can use light signals to communicate with the Earth with the same success as radio signals.

The telescope was installed at the Massachusetts Observatory and cost over $400,000, much less than the cost of a conventional research telescope. Interest in the SETI project has grown, and many hopes are pinned on it.

Since 1995, within the framework of the SETI project, a distributed computing project has begun its work. [email protected] It involves the participation of volunteers who must provide the free resources of their home computers to process signals collected from space.

Now, by registering on the project website, the participant can even improve the code of the programs used to decode and process the digital signal from the Allen telescopes. Experts with programming skills can study the processed data in a collective search for possible signals of artificial origin.

At the annual conference in California, which took place in 2010, a prize was awarded for disseminating worthy ideas in this area. It was received by astronomer Jill Tarter, she wished that all earthlings had the opportunity to become active participants in the search for extraterrestrial civilizations. In the same year, in honor of the 50th anniversary of the search for intelligent life in the universe, the inhabitants of the UK had the opportunity to send messages to extraterrestrial civilizations. All citizens over the age of 16 who wished to send this message filled out a form on the Penguin website of no more than 40 words. The first few thousand messages were sent into space using a radio telescope, and the authors of the most interesting messages received a book by the theoretical physicist Paul Davies, Ominous Silence: Are We Alone in the Universe?, dedicated to the SETI project. The announcements were of various content, including some humorous ones, such as “Attractive life form, wondering if she is alone in the universe, wants to meet other life forms for a serious relationship. You need to have a good sense of humor."

Have you ever thought that humanity is not alone in the Universe? That among the millions and billions of stars that make up its visible part, there must be systems in which there is intelligent life...

We invite you to take part in the project to search for signals from extraterrestrial civilizations! How can you do it? Download , install and run software BOINC, which uses [email protected] When prompted, enter the URL: http://setiathome.berkeley.edu and join to our team [email protected]- Connecting Worlds.

SETI (Search for Extraterrestrial Intelligence, or Search for Extraterrestrial Intelligence in Russian) is a scientific direction, the purpose of which is to detect intelligent life outside the Earth.

The principle of the search is simple: the signals received by the Arecibo radio telescope are divided into small segments and analyzed on the computers of the project participants.
The purpose of the analysis is to find signals with special characteristics, since such signals may have an artificial extraterrestrial origin.
The data received from the feed of the radio telescope is recorded at high density on magnetic tape (filling approximately one 35-gigabyte DLT tape per day). During processing, the data from each tape is divided into 33,000 blocks of 1,049,600 bytes each, which is 1.7 s of the recording time from the telescope. Then, 48 blocks are converted into 256 calculation tasks, which are sent to at least 1024 computers of the project participants (one task is processed simultaneously on at least 4 computers). After processing, the results are transmitted by the project participant's computer to the Space Sciences Laboratory (SSL) of the University of California, Berkeley (USA), using the BOINC software.

BOINC - Open Infrastructure for Distributed Computing at Berkeley University (Berkeley Open Infrastructure for Network Computing) - a software platform for organizing distributed computing (distributed computing is a way to perform any complex calculations by dividing them between many computers) using voluntarily provided computing resources. The program is developed by the University of California at Berkeley (University of California, Berkeley). All BOINC sources are available under the LGPL license, so the program can be used on almost any modern operating system. There are ready-made binary distributions of the program for operating systems Windows®, Linux, Mac OS X, Solaris.

If the project detects such a signal, then the participants whose computers were processing units (tasks) containing the signal will be listed as co-authors of all subsequent scientific publications.

The requirements for participating computers are quite modest by today's standards. For example, slowly but surely, the SETI client will work on a machine with a Pentium 160 MHz 64 Mb RAM, and even on a weaker one, as long as the operating system works. There are versions for MacOs X, and for Linux, and for Solaris. Participants do not pay any money for participation in the project, but they do not receive any bonuses either.

For the processor time spent on searching for signals, the project participants receive the so-called "credit" (credit). This number allows you to evaluate both your contribution to the common cause and the performance of your computer. The unit of measure is cobblestone. 1 Cobblestone corresponds to one hundredth of the amount of computation performed in one day by a computer that, according to benchmarks, has a performance of 1 billion floating point operations per second and 1 billion integer operations per second. Simply put: 1 Cobblestone = (1 GigaFlop per second + 1 GigaCelope per second) * day / 100.

Start

It all started in 1959, when two physicists at Cornell University, Giuseppi Cocconi and Philip Morrison, published an article in the journal Nature that indicated the possibility of using microwave radio emission as a means of interstellar communication.

Regardless of them, the then young radio astronomer Frank Drake came to the same conclusion. In 1960, he first made the first search for signals from possible brothers in mind.

For two full months, Drake sat near an 85-foot radio telescope in West Virginia, pointing at two nearby sun-like stars. The receiver was tuned to 1420 MHz in the neutral hydrogen spectrum line. This frequency was mentioned with a warm word by both Cocconi and Morrison.

Nevertheless, Drake's Ozma project aroused considerable interest, including among our compatriots. As reported on the official website of the SETI Institute, in the 1960s, it was the USSR that dominated this program.

Moreover, Soviet telescopes were not focused on any specific stars. Instead, omnidirectional antennas were used to scan large swaths of the sky in the hope of finding signs of at least a few advanced civilizations capable of sending out powerful microwave signals.

In the early 1970s, NASA's Ames Research Center began exploring the technologies needed for efficient search. An outside team led by Bernard Oliver conducted a NASA-specific research work, codenamed Project Cyclops.

This report addressed the scientific and technological issues associated with SETI and it was this paper that became the basis for all further work within the initiative.

Gradually, confidence grew in the scientific community that the SETI initiative would sooner or later be crowned with success - and what else is needed in this case? Naturally, a new wave of interest in "aliens" began in America.

Some of the programs started in the 1970s are still active today. Luckily, technology is different now.

Among these veterans are the Planetary Society's Project META META project, the University of California's SERENDIP project, and the Ohio State University's longstanding stargazing program.

By the late 1970s, the Ames Research Center and NASA's Jet Propulsion Laboratory (Jet Propulsion Laboratory) came to grips with SETI programs.

The following strategy was proposed: the Ames Center conducts an address search, examining about a thousand sun-like stars for weak signals. JPL is engaged in a systematic review of the entire sky.

In 1988, NASA Headquarters, after a decade of studying the proposed strategy, formally approved the plan and began funding the program.

Four years later, on the 500th anniversary of Columbus's arrival in the New World, research did begin. And a year later, Congress cut off oxygen to the program.

But it was not there. As you know, cadres decide everything, and these same cadres - scientists and just interested people, got together and organized the SETI Institute, which is funded by private individuals.

At the head of the SETI Institute is the same Frank Drake, the creator of the main, perhaps, ideological product that whips up interest in the search for extraterrestrial life. He calculated its probability.

In 1964-84 he worked as the director of the same Arecibo radio observatory, which is now the hope and pillar of the program. [email protected]

As already mentioned, in 1960 he made the world's first search for radio signals from brothers in mind - unsuccessful, like all subsequent ones.

And in 1961, he deduced the very famous "Drake formula", which describes the probability of finding intelligent life. The formula looks like this:

N = R* f p n e f l f i f c L

Where:

N is the number of civilizations in our Galaxy whose electromagnetic signals can be detected;

R* is the number of stars near which intelligent life can arise;

f p is the proportion of stars with planetary systems;

n e is the proportion of planets per planetary system where conditions suitable for the origin of life may be present.

f l is the proportion of planets suitable for life, on which it actually originated;

f i is the proportion of habitable planets where intelligent life is born;

f c is the proportion of civilizations that have technologies that allow them to send signals into space that are distinguishable by other civilizations.

L is the time interval in which a civilization sends such a signal into space.

There are about 400 billion stars in our galaxy. So the optimism of Soviet researchers was quite understandable. However, it should be taken into account that all these f and n are coefficients less than one. These are shares. And the coefficient L is especially important ...

A new version of the Drake equation for counting civilizations in the multiverse has also been proposed. It adds several additional parameters to the classic Drake equation. At the same time, the researchers proceeded from the assumption that humanity is only interested in civilizations that in many ways resemble ours.

Among the new parameters, for example, there is one corresponding to the extent to which the laws of such parallel universe reminiscent of ours. In addition, parameters have appeared that characterize the size of galaxies where life can appear. Scientists emphasize that the modified Drake equation has the same drawback as its classical counterpart - the parameters included in it cannot be estimated with current knowledge of space. Thus, the new work is of little use in a realistic assessment of the probability of finding brothers in mind.

Recently, Frank Drake proposed a new way to look for signals from other civilizations. Signals that come to Earth from very distant objects are often very weak, and telescopes cannot detect them.

To get around this difficulty, Drake proposed using the phenomenon of gravitational lenses, or Einstein lenses. The theory of relativity postulates that massive objects bend space-time around them. When a beam of light passes near such objects, its path is also curved. Under certain conditions, this property allows, as it were, to increase the observed objects.

To catch such "magnified" signals, the telescope must be located at a certain point, remote from the Earth at a distance of about 82 billion kilometers.

The idea proposed by Drake is not new, but so far no one has proposed putting it into practice. The reason for the skepticism is too much distance that the telescope will have to overcome.

[email protected] is a logical continuation of the SETI program.

So, the essence of the program is that the underlying data received by the Arecibo radio telescope are distributed all over the world - millions of computers perform individual computational operations, after which the results are "merged" back and subjected to further analysis.

Obtaining results is the most resource-intensive process that requires huge computing power, so distributed computing turns out to be just the salvation here.

Saving for the whole SETI extraterrestrial intelligence program, the idea of ​​​​creating a distributed computing network came to the smart minds of David Gedye and Craig Kasnoff. They developed a scientific plan and presented it at the Fifth International Conference on Bioastronomy in July 1996.

The project was accepted with a bang. The following year, a program code was developed that, in fact, does the main job: it analyzes the noise from the Arecibo telescope in search of what could be a signal from other civilizations.

Development of server and client software continued until 1999.May 17, 1999 of the year the official launch of the project.

The PR-calculation turned out to be extremely successful, even more successful than the creators of the program expected. Everyone is invited to help science, while everyone has a small chance to become the very person who caught the signals of an alien civilization.

And all this without leaving home. Or from work. Moreover, calculations do not require a lot of resources, even if the client is graphical and designed for a screensaver (in fact, the screensaver displays the work of the main program that performs calculations).

In fact, your computer is engaged in "filtering", filtering individual fragments of the noise received by Arecibo, and searching for "golden grains" in it.

At some point, the organizers of the program were even afraid that the data would begin to arrive slower than they could be processed.

I must say that within the framework of the SETI project, 93% of the sky was "listened", however, in a very narrow range.

In addition, there is a SETI program called Phoenix, which is much more targeted at tracking supposed sources of extraterrestrial intelligence signals. Several star systems have been selected for it, in which, according to astronomers, the presence of life is most likely, and it is these systems that will be "listened".

On January 27, 2009, the creation of a new open source project was announced − setiQuest .

Participants of the project to search for extraterrestrial civilizations SETI on the project website setiQuest have already opened the existing project data to the public.

In addition to getting acquainted with the information, everyone will be able to improve the existing signal processing algorithm for the search for extraterrestrial life, since its source codes will be disclosed on the site.

Idea to make project data [email protected] open belongs to project leader astronomer Jill Tarter. In 2009, Tarter was the recipient of the TEDPrize Award for the best "wish that can change the world." The award was created by the participants of the TED project (Technology, Entertainment and Design - technology, entertainment and projects). Within the framework of the project, conferences are held annually, during which famous people lectures on various topics.

Will we find extraterrestrial intelligence before 2025?

Chief astronomer of the project to search for extraterrestrial intelligence [email protected] Seth Shostak believes such intelligence could be discovered by 2025. However, the scientist emphasizes that the forecast will come true only if microelectronics continues to develop according to Moore's law.

Moore's Law suggests that the performance of computer processors doubles every 18 months. At present, the microprocessor industry is developing in accordance with this law. Shostak believes that if this trend continues, then by 2025 radio telescopes will be able to "hear" what is happening in outer space at a distance of 500 light-years from Earth (a light year corresponds to the distance that light travels in a year). In this case, the probability of detecting a signal produced by other intelligent beings is very high.

The last conclusion is made on the basis of the same Drake formula. With a certain value of the parameters, it assumes that about ten thousand intelligent civilizations capable of creating radio transmitters live in our Galaxy.

The main device that the project participants hope for [email protected], is the Allen Telescope Array telescope system. It was created with the participation of one of the founders of Microsoft Paul Allen (Paul Allen). If Moore's law continues to operate, by 2025 the system of telescopes will reach the required power.

Problem - Mountains of data

Most current SETI programs, including those at UC Berkeley, use large computers that analyze telescope data in real time. None of these computers look too deep into the data for weak signals, or look for a wide class of signal types (we'll discuss those in a bit...) The reason for this is the limited power of the computers available to analyze the data. The search for the weakest signals requires very large computing power. Doing the job will require a giant supercomputer. The SETI programs could never afford to build or purchase such computing power. However, they can make a detour. Instead of a large computer doing work, they can use a smaller computer that will last longer. However, in this case, piles of raw data will accumulate. What if there are LOTS of small computers running different parts of the analysis at the same time? Where could the SETI team find the thousands of computers needed to analyze the data streaming in from Arecibo?

The SETI team at UC Berkeley found that there are already thousands of computers that could be used. Most of these computers sit idle while toasters fly on their screen and do absolutely nothing but waste electricity. That's where the scene appears [email protected](and you!). Project [email protected] hopes to persuade you to let us use your computer while you are not using it and help us "...seek new life and new civilizations." We will do this with a screen saver that will be able to get a piece of data from us over the Internet, analyze the data and send the result back to us. As soon as you need your computer again, our screen saver immediately moves out of the way and continues the analysis only when you are done.

This is an interesting and difficult task. There is so much data that it seems impossible to analyze them! Fortunately, the task of data analysis is easily broken down into small pieces, each of which can be processed separately and in parallel. None of the pieces depend on the others. In addition, only the final part of the sky is visible from Arecibo. Over the next two years, the entire sky visible to the telescope will be scanned three times. We think that this is enough for this project. By the time we thrice scan the sky, there will be new telescopes, new experiments, and new approaches to SETI. We hope that you will be able to participate in them too!

Breakdown of data

Data is recorded at high density on tape at the Arecibo telescope in Puerto Rico, filling approximately one 35GB DLT tape per day. Arecibo doesn't have a broadband internet connection, so the data is sent by regular mail to Berkeley. The data is then split into chunks of 0.25 megabytes (which we call "work units"). They are sent over the Internet from the server [email protected] people around the globe to process.

How data is broken into chunks

[email protected] scans data in the 2.5 MHz band around 1420 MHz. This spectrum is still too wide for you to analyze, so we split this band into 256 chunks, each 10 kHz wide (to be precise, 9766 Hz, but we'll round the numbers for ease of calculation). This is done by a program called a splitter. The resulting 10 kHz chunks are somewhat easier to handle. Recording a signal up to 10 kHz requires 20 thousand bits per second (kbps). (This is called the Nyquist frequency.) We send you about 107 seconds of this 10 kilohertz (20kbps) data. 100 seconds multiplied by 20,000 bits equals 2,000,000 bits, or about 0.25 megabytes, given that there are 8 bits in a byte. Once again, we call these 0.25 MB chunks "work units". We also send you a lot of additional information about the work unit, resulting in about 340 kilobytes of data.

Data forwarding

[email protected] requires a connection for data transfer only. This only happens when the screen saver has finished parsing a work unit and wants to send the results back (and receive a new work unit). This happens only with your permission, and you can control when your computer communicates with us. If desired, you can specify in the screen saver settings that data should be transferred automatically, immediately after processing the next work unit. Data transmission through the most common dial-up modems takes less than 5 minutes, and the connection is terminated immediately after all data has been transferred.

All work units are accounted for in a large database here at Berkeley. Even though the work unit data overlaps slightly to make sure nothing is missed, no two people will get the same work unit. When a work item is returned to us, it is attached to the database and marked as "processed". Our computers find the new work item, send it to you and mark it in the database as "in process". If there is no news from you for a long time, we assume that you have abandoned us (and you, by the way, should be very ashamed!), and someday your unfinished work will go to someone else.

What is looking for [email protected]?

So what are you going to do for us? What exactly will you be looking for in the submitted data? The easiest way to answer this question is by telling us what kind of signals we expect from aliens. We expect them to send us a signal in the most efficient way possible for THEM to allow us to easily identify the message. So, it turns out that sending a message at once on many frequencies is inefficient. This requires very high power. A message with energy concentrated in a very narrow frequency range is easier to identify against a background of noise. This is especially important since we assume that they are far enough away from us that their signal will become very weak once they reach us. So, we are not looking for wideband signals (distributed over many frequencies), we tune the radio receiver to different channels and look at the signal strength on them. If the signal is strong, it draws our attention.

Another factor that makes it possible to eliminate local (terrestrial and satellite) signals is their more or less constancy. They do not change intensity over time. On the other hand, the Arecibo telescope is stationary. During work [email protected] The telescope does not follow the stars. As a consequence, the sky "floats" over the focus of the telescope. The target passes the focus of the dish in about 12 seconds. Therefore, we expect that the extraterrestrial signal will first become stronger for 12 seconds, and then weaken. In search of this 12 second "gaussian" signal, we send you about 10 seconds of data. In addition, the data in different working units overlap slightly so that important signals are not cut off early in the analysis.

Let's look at a few examples.

On this graph (as well as on all subsequent ones), time is plotted horizontally. The signal frequency is plotted vertically. Here is a wideband signal in which many frequencies are mixed. Notice how the signal starts out weak (dim) on the left, gets louder (brighter), peaks at the center of the graph after 6 seconds, and weakens over the next 6 seconds. This is the behavior we expect from an extraterrestrial signal floating above the telescope. Unfortunately, we do not consider wideband signals. So, most likely, stars and other natural astronomical objects will look like. We discard broadband signals.
This graph is more like what we are looking for. Here the frequency range of the signal is much narrower. It also increases and then weakens over 12 seconds. We do not know how narrow the frequency of the bands will be, and therefore we are looking for signals in several bands.
If our star friends try to transmit some information with the signal (which is very likely), the signal will almost certainly be modulated. We are also looking for such signals.
It is unlikely that our planetary systems are motionless relative to each other. This relative motion can cause a "Doppler shift", or change in signal frequency. Because of it, the frequency of the signal within 12 seconds may slightly increase or decrease. Such signals are called "chirped", and we are also looking for them.
Of course, we are also interested in chirped modulated signals!

Analysis Details

Program [email protected] searches for signals 10 times weaker than those searched for by SERENDIP IV in Arecibo, as it uses a computationally cumbersome “coherent integration” algorithm. No one else (including the SERENDIP program) has the computing power to implement this method. Your computer performs a Fast Fourier Transform on the incoming data, looking for strong signals at various combinations of frequency, bandwidth, and chirp. The following operations are carried out on each of the working units sent by us.

Consider first the most time-consuming part of the calculations. First, the data must be "chirped" - to eliminate the effects of the Doppler shift. At the highest resolution we have to do this 5000 times, from -5 Hz/s to +5 Hz/s in .002 Hz/s steps. For each chirp value, 107 seconds of data is chirped and then divided into 8 blocks of 13.375 seconds each. Each 13.375 second block is tested with a bandwidth of .07 Hz for spikes (i.e. 131,072 checks (frequencies) per block per chirp amount!) That's a LOT of calculations! During this first step, your computer performs about 100 billion operations!

We are not finished yet, we need to check other stripe widths. At the next stage, the bandwidth is doubled to 0.15 Hz. Starting from this bandwidth, we double the range of possible chirps to -10 Hz/s to +10 Hz/s. Although this doubles the range, we only need to test 1/4 of the possible chirps since the band got wider. In total, we have twice the range of possible chirps, but we only look at a quarter of them. In total, we will do about half the amount of work that we needed at the highest resolution (narrow bandwidth), or about 50 billion operations.

In the next step, we again double the bandwidth (from 0.15 to 0.3 Hz) and again quadruple the number of chirps under consideration. (We keep the chirp range from -10 Hz/s to +10 Hz/s throughout all subsequent calculations.) This (and all subsequent) steps require four times less calculations than the previous one. In this case, it is only 12.5 billion operations. This continues for 14 doublings of the bandwidth (0.07, 0.15, 0.3, 0.6, 1.2, 2.5, 5, 10, 20, 40, 75, 150, 300, 600 and 1200 Hz), giving a total of just over 175 billion operations on 107 seconds of data. As you can see, most of the work is done at the narrowest bandwidth (about 70% of the work.)

Finally, signals that are strong in some combination of frequency, bandwidth, and chirp are checked to see if they are interference from the Earth. Only signals that rise and fall within 12 seconds (the time it takes for a patch of sky to pass over the telescope) are tentatively considered extraterrestrial in nature.

How long does all these calculations take? On average, a rather weak home computer (with a processor running at about 233 MHz) will spend about 24 hours calculating one working unit. This figure is obtained from the calculation that the computer is busy ONLY with calculations. [email protected], and not even your favorite game. Don't forget, too, that we get more than 200,000 work units of new data every day!

Now you know why we need your help!

What will happenif my computer detects aliens?

Before you get to the “what will happen”, you need to deal with the “what if”. In considering this data and the results of your analysis, it is very important to remember that there are SO many sources of radio signals. Many of them are born on Earth thanks to TV stations, radars and other high frequency transmitters. Satellites and many astronomical objects are also sources of signals. There are also "test signals" specifically introduced into the system so that the command [email protected] could make sure that the hardware and software functions correctly at all stages of work. The Arecibo radio telescope will collect all these signals and happily send them to your client for processing. The radio telescope doesn't care what the signals are. Like your ear doesn't care what it hears. Your client program will sift through these signals looking for one that is "louder" than the background, and that fades in and out over the course of 12 seconds, the time it takes for a patch of sky to pass over the telescope.

All relevant signals will be sent back to the Berkeley team. [email protected] for further analysis. Team [email protected] maintains a large database of known sources of radio interference (IEP). This database is constantly updated. At this point, 99.9999% of all signals detected by clients are discarded as IEDs. Test signals are also discarded.

The remaining unidentified signals are compared with other observations of the same area of ​​the sky. This may take up to 6 months as the team [email protected] does not control the telescope. If the signal is confirmed, the command [email protected] will require the telescope's allocated time and re-scan the most interesting candidates.

If the signal will be observed two or more times, and it will not be a test or IEP signal, the command [email protected] will ask another group to check it. This group will use a different telescope, different receivers, computers, etc. In this way, we hope, failures in our hardware or software will be eliminated (and overly smart students trying to prank us ...) Together with the second group, the team [email protected] will make interferometric measurements (this requires two observations with instruments separated by a greater distance). This will confirm that the source of the signal is at an interstellar distance.

If this is confirmed, [email protected] will make a statement in the form of an IAU (International Astronomical Union) telegram. This is the standard way of notifying the astronomical community of important discoveries. The telegram will contain all important information(frequencies, bandwidth, sky coordinates, etc.) needed by other groups of astronomers in order to confirm the observation. The one(s) whose client program detected the signal will be named among the co-discoverers along with other team members [email protected] At this stage, we still won't know for sure whether the signal is sent by an intelligent civilization or comes from some new astronomical phenomenon.

All information about the discovery will be made public, probably over the Internet. No country or individual will be allowed to jam the frequency on which a signal has been detected. From the point of view of any particular observer, the object will rise and set, therefore, observation from radio observatories around the world will be required. Thus it will be, of necessity, a multinational enterprise. All this information will also become public domain.

Declaration of principles regarding actions following the discovery of extraterrestrial intelligence.

We, organizations and individuals involved in the search for extraterrestrial intelligence, recognizing that the search for extraterrestrial intelligence is an integral part of space research and undertaken for a peaceful purpose in the interests of all mankind, inspired by the great significance that the discovery of extraterrestrial intelligence has for humanity, although the probability of detection may be low , meaning the “Treaty on the Principles for the Regulation of the Activities of States in the Exploration and Use of Outer Space, Including the Moon and Other Celestial Bodies”, which prescribes to the states parties to this treaty<... информировать Генерального Секретаря Организации Объединенных Наций, а также общественность и международное научное сообщество «для наиболее широкого возможного использования» о природе, месте, проведении и результатах>their activities in space exploration (Article XI), recognizing that any initial discovery may be incomplete or unclear and requires careful verification and confirmation, and that it is especially important to maintain the highest standards of scientific responsibility and credibility, have agreed to abide by following principles dissemination of information about the discovery of extraterrestrial intelligence:

1. Any individual researcher, public or private research institution, or government agency who believes that they have discovered a signal or other evidence of the existence of extraterrestrial intelligence (the Discoverer) should, before making a public statement, make sure that the most acceptable explanation is the existence of extraterrestrial intelligence rather than any other natural or man-made phenomena. If proof of the existence of extraterrestrial intelligence cannot be established with certainty, the Discoverer may spread the information as relating to the discovery of some unknown phenomenon.

2. Before making a public announcement that evidence has been obtained for the existence of extraterrestrial intelligence, the Discoverer should promptly inform all other observers and research organizations that are parties to this Declaration so that they can confirm the discovery with independent observations from other places, and a network can be created , which enables continuous monitoring of a signal or phenomenon. Declaration participants should refrain from any public presentation of information until it has been determined whether this information is conclusive evidence of the existence of extraterrestrial intelligence. The discoverer should inform his national authorities.

4. Confirmed news of the discovery of extraterrestrial intelligence must be disseminated quickly, openly and widely through scientific channels and through the media in accordance with the procedures of this Declaration. The discoverer should be given the right to make the first public statement.

5. All data necessary for validation should be made available to the international scientific community through publications, meetings, conferences and other possible means.

6. In order for a discovery to be confirmed and controlled, any data relevant to the discovery must be recorded and permanently stored for the widest possible use in a form accessible for later analysis and interpretation. These records should be made available to the international institutions listed above and members of the scientific community for the purpose of objective analysis and interpretation.

7. If the detection data is in the form of an electromagnetic signal, the parties to this Declaration shall reach an international agreement to protect the frequencies concerned by applying the procedures provided for by the International Telecommunications Union (ITU). A message should be sent immediately to the ITU Secretary General in Geneva, who can include in the Weekly Circular a request to reduce the number of transmissions on the indicated frequencies. The Secretariat, together with the notification of the Administrative Council of the Union, should investigate the possibility and expediency of convening an Extraordinary Administrative Radio Conference to consider this issue, taking into account the views of the members of the administration of the ITU.

8. No response to a signal or other evidence of the existence of extraterrestrial intelligence can be sent before special international consultations. Procedures for such consultations will be defined in specific agreements, declarations or documents.

9. The SETI Committee of the International Academy of Astronautics [IAA], in conjunction with Commission 51 of the International Astronomical Union, will continuously review procedures for the detection of extraterrestrial intelligence and the subsequent use of data. If a credible indication of the existence of extraterrestrial intelligence is obtained, an international committee of scientists and other experts should be established to serve as a center for continuous analysis of all collected observational data, as well as to recommend information for the release of information to the public. This committee should be composed of representatives of the international institutions referred to above, as well as other members as may be necessary. In order to facilitate the convening of such a committee (if a discovery occurs), the IAA SETI Committee should establish and maintain a current list of future representatives of each of the indicated international institutions and selected individuals who may be eligible; it is necessary that the list be constantly available to the IAA Secretariat. The IAA will act as the Depositary of the Declaration and will provide the current list to all its members annually.

The official Declaration of Principles Concerning Action Following the Discovery of Extraterrestrial Intelligence is available at this link.

Because of this protocol, it is very important that project participants [email protected] weren't overjoyed at finding the signals on their screen, and didn't rush to make their own statements and call the press. This can greatly damage the project. So let's keep our heads cold and our computers hot and let them grind data. Each of us can hope that he will be the one who will help get a signal from some extraterrestrial civilization trying to "call us."

Caught something in the SETI "network"?

August 15, 1977 while working on the Big Ear radio telescope at Ohio University, Dr. Jerry Ehman discovered a strong narrow-band cosmic radio signal - signal "Wow!"(Wow!), also sometimes referred to in Russian publications as the “Wow!” signal. Signal characteristics (transmission bandwidth, signal-to-noise ratio) corresponded to theoretically expected from a signal of extraterrestrial origin.

circled code 6EQUJ5 shows the change in the intensity of the received signal over time. A space on the printout meant intensity from 0 to 0.999..; figures 1-9 - intensity from the corresponding intervals from 1.000 to 9.999 ...; intensity, starting from 10.0, was coded by letters (thus, "A" meant intensity from 10.0 to 10.999…, "B" - from 11.0 to 11.999…, etc.). The letter "U" (intensity between 30.0 and 30.999…) was encountered only once during the entire time of the radio telescope's operation. Intensities in this case are dimensionless signal-to-noise ratios; the noise intensity in each frequency band was taken as the average value over the previous few minutes.

The signal width was no more than 10 kHz (since each column on the printout corresponded to a 10 kHz bandwidth, and the signal is present in only one single column). Various methods for determining the frequency of the signal gave two values: 1420.356 MHz (J. D. Kraus) and 1420.456 MHz (J. R. Ehman), both within 50 kHz of the hydrogen line frequency (1420.406 MHz, or 21 cm.)

Struck by how closely the characteristics of the received signal matched the expected characteristics of the interstellar signal, Eyman circled the corresponding group of characters on the printout and signed "Wow!" ("Wow!"). From this signature came the name of the signal.

Determining the exact location of the signal source in the sky was difficult due to the fact that the Big Ear radio telescope had two feeds oriented in several different directions. The signal was received by only one of them, but the limitations of the data processing method do not allow us to determine which feeder fixed the signal. Thus, there are two possible values ​​for the right ascension of the signal source:

• 19 h 22 m 22 s ± 5 s (positive feed)
• 19 h 25 m 12 s ± 5 s (negative feed)

The declination is uniquely determined at −27°03′ ± 20′ (values ​​are presented in epoch B1950.0 ).

When converted to epoch J2000.0, the coordinates correspond to PW= 19 h 25 m 31 s ± 10 s or 19 h 28 m 22 s ± 10 s , and declination −26°57′ ± 20′

This region of the sky is in the constellation Sagittarius, about 2.5 degrees south of the fifth magnitude star group Chi Sagittarius.

The Big Ear radio telescope does not have a mobile receiving antenna, and uses the Earth's rotation to scan the sky. Given the angular velocity of this rotation and the limited width of the antenna reception area, each point of the sky can only be observed for 72 seconds. Thus, an extraterrestrial signal of constant amplitude should be observed for 72 seconds, while for the first 36 seconds its intensity should gradually increase - until the telescope is pointed exactly at its source - and then for another 36 seconds it should also decrease smoothly, as the rotation of the Earth leads the listening point of the celestial sphere out of the reception area.

Thus, both the duration of the "wow" signal (72 seconds) and the plot of its intensity over time correspond to the expected characteristics of an extraterrestrial signal.

It was expected that the signal would be registered twice - once by each of the irradiators - but this did not happen. For the next month, Eiman tried to re-register the signal with the Big Ear, but to no avail.

In 1987 and 1989, Robert Gray tried to detect the signal with the META array at the Oak Ridge Observatory, but was unsuccessful. In 1995-1996, Gray again took up the search with the much more sensitive Very Large Array radio telescope.

Gray and Dr. Simon Ellingsen subsequently searched for a repeat in 1999 using the 26-meter Hobart radio telescope at the University of Tasmania. Six 14-hour observations of the vicinity of the alleged source did not find anything resembling signal repetitions.

As one of the possible explanations, the possibility of random amplification of a weak signal is proposed; however, on the one hand, this still does not exclude the possibility of an artificial origin of such a signal, and on the other hand, it is unlikely that a signal weak enough to not be detected by the supersensitive Very Large Array radio telescope could be caught by the Big Ear even after such amplification. Other assumptions include the possibility of rotation of the source of radiation like a beacon, a periodic change in the frequency of the signal, or its one-time. There is also a version that the signal was sent from a moving alien starship.

Eiman expressed doubts that the signal was of extraterrestrial origin: " We had to see him again, looking for him fifty times. Something suggests that it was a signal of terrestrial origin, which was simply reflected from some piece of space debris."

He later partially abandoned his initial skepticism when further research showed that such an option was extremely unlikely, since such a proposed space "reflector" would have to meet a number of completely unrealistic requirements. In addition, the frequency 1420 MHz is reserved and is not used in any radio transmitting equipment. In his latest writings, Eyman prefers not to "draw far-reaching conclusions from very narrow-minded data".

About another signal from spacethe chief scientist of the project, astronomer from the University of California at Berkeley (UC Berkeley) Dan Wertimer (Dan Werthimer) said that"this is the most interesting signal in the history of the program [email protected] , we are not jumping to the ceiling for joy, but we continue to watch him."

From the huge mass of "raw" material collected by the Arecibo radio telescope during the existence of the project [email protected] several million candidate signals have been identified, most likely of artificial origin. All of them were subjected to verification, repeated observations and analysis, as a result of which approximately one and a half thousand of the most suspicious remained. March 2003 to April 2004 a general check was carried out, sifting out all the signals in general, except for one. By the way, you can see the new top 10 candidates. Here it is worth noting that the leadership of SETI, despite the obviously public nature of the project and promises to disclose all important findings, acts quite covertly and inertially. Once every few months, official news reports (newsletters) are published. It was in one of these reports that they talked about some mysterious signal that passed all the tests, however, it is described in very general terms, even without indicating a code name (SETI adopted its own system for identifying candidate signals). There is also a promise to "follow him further." And everything - since then, not a word.

Of course, the SETI leadership is understandable: they are certainly trying their best to avoid the empty hype that the popular press can raise. But after all, could they at least describe the find more accurately and tell about the ongoing work? Fortunately, there were journalists who did it for them: apparently, the article published in the paper New Scientist is devoted to this mysterious signal in all respects.

The signal appears in the general list compiled by SETI under the name SHGb02+14a(hereinafter SHG). He came from a point in the sky, located between the constellations of Pisces and Aries. He was observed three times: the first two times he was isolated by computers of ordinary SETI participants, the third time he was caught by the project's staff members. The base signal frequency is about 1420 MHz, and it does not remain constant - it "drifts" at a rate of 8 to 37 Hz per second. Actually, that's all that is known about SHG. The following are only suggestions put forward by the researchers themselves at SETI and by third-party astrophysicists who analyzed the signal. Arecibo held the signal for a total of a minute - this is not enough for a detailed analysis. But researcher Eric Korpela doubts that SHGb02+14a is the result of radio interference or terrestrial noise. The signal has no "signature" of any of the known astronomical objects.

So, SHG could not be attributed to any of the processes known to science - on Earth or in space. Therefore, the version with interference from ground equipment (perhaps somewhere near the Arecibo telescope is something that emits in the 1420 MHz band, and the moving components of the radio telescope antenna pick up this signal at a certain point) seems untenable. What kind of cosmic cataclysm can generate SHG is also unknown. Moreover, at a distance of a thousand light-years, which is the approximate radius of SETI's "safe reception of artificial signals", in the direction from which SHG is coming, space is empty. Finally, for some unknown reason, in each observation, SHG "started" at 1420 MHz, as if the signal source "knew" when a radio telescope was pointed at it.

All this, and especially last fact, raises doubts among scientists that SHG really came from space. It is possible that the source of the signal is actually hidden in the radio telescope itself, in some unaccounted for feature of it, which generates strange impulses.

The second most important theory of the origin of SHG is a process unknown to astrophysicists in deep space. This point of view is shared, in particular, by the Englishwoman Jocelyn Bell - the one who worked in the 60s on one of the first radio telescopes and stumbled upon a mysterious signal, which at first was considered the creation of an alien mind, but later turned out to be a product of the then unknown type of stars - pulsars.

There is a possibility that the signal is the tricks of hackers who hacked the software [email protected] However, SHGb02+14a was seen on two occasions by different users [email protected], and these calculations have been confirmed by others. And for the third time - not by users, but by the researchers themselves. In addition, the unusual properties of the signal make the joke unlikely: a method for this kind of falsification has yet to be invented.

The fourth and most incredible theory is the artificial origin of SHG. Imagine the world of an alien star with a system of planets similar to the Sun. Their sun has been dead for billions of years, and perhaps the civilization is also dead or gone to other luminaries. Only the galactic beacon is alive, where their ships once laid their course. The "starting" frequency and frequency drift of the mysterious SHG can be explained in this way. Of course, all this is very similar to the "black" science fiction of the 20th century, but you are not really expecting an ASCII-encoded package with text " hello earthlings"?!

Where are you brothers in mind?

Recently, astrophysicists built a numerical model of the development of civilizations in the Galaxy and found out that the probability of establishing a connection with an alien civilization is extremely small. An article by scientists appeared in the journal International Journal of Astrobiology, and its summary is given by Universe Today.

As part of the study, the evolution of the galaxy was modeled. The first stage was the formation of stars. Then, at random (according to some predetermined distribution), luminaries were selected from them, around which planetary systems began to form. Within the framework of the model, scientists proceeded from the assumption that life can form only in conditions resembling those on Earth.

So, they believed that for life, aliens need a planet with a mass of 0.5-2 Earth, which moves around a star with a mass of 0.5-1.5 solar. At the same time, the planet must have a satellite that will ensure the stability of the orbit, as well as a giant neighbor with a mass of at least 10 terrestrial ones in outer orbit. The task of the latter will be to protect the planet from asteroids - in the solar system Jupiter does this.

Calculations have shown that hundreds of intelligent civilizations can exist in the Milky Way. In this case, however, the probability that they will exist simultaneously - necessary condition for the emergence of communication between them is extremely small. As the moment of the end of the existence of civilization, scientists considered the moment of the transformation of a star into a red giant ...

Instruments and devices of the SETI project

Radio telescope "Big Ear". "Big Ear" no longer exists. In 1983, the land on which it was located was sold by the owner, Ohio University, to some farmers. I mean, businessmen on the ground. In 1997, the telescope stopped working, and in 1998 it was destroyed. Only photographs and a memorial site remained - http://www.bigear.org/. And in its place is now a golf course ... This telescope has long been the main source of signals for the SETI project.
After the Big Ear, the main source of signals for SETI was the Arecibo radio telescope, located in micro-quasars, radio coronas around stars and many other studies.

The Allen Telescope Array (ATA), the world's first radio telescope built specifically to search for alien civilizations.ATA is a joint venture between the Institute for the Search for Extraterrestrial Intelligence (SETI Institute) and the Astronomy Laboratory of the University of California at Berkeley (Radio Astronomy Laboratory). The huge field of cups-antennas will allow mankind to move several times further the available border of the search for intelligent signals from space. On October 11, 2007, the first 42 six-meter "dishes" (out of 350 planned) were turned on and began collecting scientific data. ATA is named after Paul Allen, co-founder of Microsoft, who contributed half of the $50 million cost of the supertelescope.

You can see the list of all radio telescopes.

Project FAQ [email protected]

Do I need to know anything about science or about SETI to participate in the project?

No. All you have to do is download and install the client software.

What about security?

This program will download and upload data only from our data server in
Berkeley. The data server does not upload any executable code to your
a computer. In general, this program will be significantly safer than
the browser you are currently using!

Will I introduce any virus if I take part in the project?

In distributed computing projects, he accepts as volunteers
participation of a huge number of people from all over the world. If one of the projects starts
spread the virus, then a large number of people will immediately know about it.
For the entire time of the existence of the RV, there was not a single case of the spread of viruses
through GRID networks. It is also worth considering the reputation of the institutions organizing such
projects they don't want to lose.

What happens if an artificial extraterrestrial signal is registered
origin?

The procedure has been agreed by SETI project researchers around the world. For
In the beginning, other SETI researchers will test the signal independently.
If it really exists and is not explained by earthly origin
(satellites, reflections, etc.) then publishing houses and governments will
this have been notified.

Will I get a promotion if the signal is registered on my
computer?

Yes. Our program keeps a record of where each fragment was made
work. If your computer participated in the discovery, then according to your
If you wish, you will be included in the list of discoverers.

How to join your team?

Section 7 NSA RAS: "Life and mind in the Universe"

Russian SETI

SETI = Search for Extra T errestrial Intelligence

Search for Extraterrestrial Intelligence

This page contains materials related to SETI activities in the USSR and Russia. Materials are given mainly in Russian in KOI8-r encoding. Some of the materials are given in English.

The materials were prepared by the Scientific and Cultural Center SETI at the Academy of Cosmonautics named after K.E. astronomy RAS).

The first sections provide information on the history of SETI in the USSR and Russia, a list of major publications, information about SETI organizations and groups.

In the "Current Materials" section, along with news, articles on SETI that have come to us are placed. This section is updated periodically, and previous articles and information about past conferences are transferred to the "Archive" section. Materials from the "News" section are also transferred to the "Archive".

The beginning of the SETI project dates back to 1959, when an article by J. Cocconi and F. Morisson "Searching for interstellar messages" was published in the international scientific journal Nature. This article showed (with an analysis of the achievable radiated power and sensitivity of radio telescopes) that even with the then level of development of radio astronomy (1959), it was possible to count on the detection of extraterrestrial civilizations of approximately the same technological level as the earth, provided that they live on planets not too far from us, in planetary systems solar-type stars.

Radio emission at a wavelength of 21 cm, a frequency of about 1420 MHz, due to a hyperfine metastable transition between two states of a neutral hydrogen atom, differing in the mutual orientation of the magnetic moments of an electron and a proton, is a universal physical quantity (the radio line of radiation of neutral atomic hydrogen in the Universe). It was assumed that any technologically advanced civilization that has reached the technological level of the earthly civilization will radiate in the radio range for contacts with other civilizations at this universal frequency. The power spectral density of interference below 1 GHz, due to the emission of fast moving electrons in the gas of the Galaxy and at frequencies above 10 GHz, which emit oxygen and water molecules in the Earth's atmosphere, is significantly higher, which makes communication difficult at interstellar distances), so this frequency was proposed in as acceptable for SETI searches.

However, the search for artificial extraterrestrial signals at this frequency and close frequencies did not lead to anything. In 1960, Frank Drake initiated the Ozma Project (named after the fairy-tale princess of Oz); signals were supposed to be searched using a 25-meter radio telescope in Green Bank, West Virginia. Two nearby solar-type stars, Tau Ceti and Epsilon Eridani, were chosen as targets for signal searches.

In 1971, NASA offered to take over funding for the SETI project. This project, also known as the Cyclops project, involved the use of one and a half thousand radio telescopes and was supposed to cost $ 10 billion. Funding was allocated for a much more modest project - to send a carefully encrypted message to space for other civilizations (see: Arecibo Message, Arecibo Observatory). In 1974, a message containing 1679 bits was sent from the giant radio telescope at Arecibo in Puerto Rico in the direction of the globular star cluster M13, located at a distance of 25,100 light-years from us. This short message is a 23 x 73 dot drawing; scientists marked on it the position solar system, placed an image of human beings and several chemical formulas. (If we take into account the distances in question, the answer can be expected no earlier than 52,166 years.

In 1995, American astronomers, due to insufficient funding from the federal government, decided to turn to private funds. A nonprofit was founded in Mountain View, California, and the Phoenix Project launched; The project involves the study of thousands of nearby solar-class stars in the 1200-3000 MHz radio band. Dr. Jill Tarter was chosen as director of the institute. This project uses extremely sensitive instruments, capable of picking up the radiation of a conventional airfield radar from a distance of 200 light years. Since 1995 the Institute SETI with a budget of $5 million a year has already scanned more than a thousand stars. But there are still no tangible results. Nevertheless, Seth Szostak, senior astronomer on the project SETI, with unfading optimism, believes that the Allen telescope system of 350 antennas "will stumble upon a signal before 2025".

An innovative approach to the problem was demonstrated by astronomers from the University of California at Berkeley: in 1999 they launched the project [email protected] . The idea of ​​the project is to attract to work millions of owners of personal computers, whose machines are simply idle most of the time. Those who participate in the project download from the Internet and install on their computer a software package that works in screensaver mode, and therefore does not cause any inconvenience to the owner. These programs are involved in decoding the signals received by the radio telescope. So far, 5 million users from over 200 countries have joined the project; together they spent more than a billion dollars worth of electricity, but it was not expensive for each user to participate in the project. This is the largest collective computer project in history; it could serve as a model for other projects that require more computing power. However, the project is still [email protected] also did not find any reasonable signal.

Techniques

There are two approaches to the search for extraterrestrial intelligence:

• Look for signals from extraterrestrial civilizations. Counting on the fact that fellow minds will also seek contact. There are three main problems with this approach: what to look for, how to look, and where to look.
• Send the so-called "ready signal". Counting on the fact that someone will look for this signal. The main problems of this approach are virtually the same as those of the first approach, except for smaller technical problems.

One approach is expressed in the NASA-funded program for listening to artificial electromagnetic signals - on the assumption that any technologically advanced civilization should come to the creation of systems of radio-television or radar signals - the same as on Earth. The earliest electromagnetic signals on Earth could by now travel in all directions over a distance of almost 100 light-years. Attempts to isolate alien signals directed towards the Earth have so far remained unsuccessful, but the number of stars “tested” in this way is less than 0.1% of the number of stars still awaiting research if there is a statistically significant probability of finding extraterrestrial civilizations.

During the 1960s-1980s, SETI was covertly funded (through science foundations) and used by the CIA for spaceborne radio intelligence—the search for frequencies that operated Soviet satellites and ground stations.

AT new job scientists proposed to look for "light" traces of extraterrestrial civilizations. So, for example, they propose to register the illumination of the night side of exoplanets, (for example, by the light of cities). Assuming the planet's orbit is elliptical, astronomers have shown that it is possible to measure the variation in an object's brightness and detect whether its dark side is illuminated. At the same time, however, scientists assume that the luminosity of the dark side is comparable to the luminosity of the daytime (for the Earth, these values ​​\u200b\u200bare different by five orders of magnitude).

In addition, scientists intend to look for bright objects in the Kuiper belts around other stars with subsequent spectral analysis of their radiation. Astronomers believe that such an analysis will determine the nature of lighting - whether it is natural or artificial. Scientists emphasize that all the proposed options are unrealizable using existing technology. At the same time, in their opinion, new generation telescopes, such as the American "James Webb", are quite capable of coping with the tasks described in the paper.

The James Webb project, which is currently experiencing serious financial difficulties, should become a successor to Hubble. The diameter of its mirror, consisting of several hexagonal segments, will be 6.5 m (Hubble's mirror is 2.4 m). The telescope itself, equipped with a protective screen, will have to be located at the Lagrange point L 2 at a distance of 1.5 million km from the planet. So far, the launch is scheduled for May 2019.

Research in the USSR

In Russia, SETI experimental research has developed in several directions:

• The search for radio signals from sun-like stars was carried out at the SAO RAS on the RATAN-600 radio telescope in the centimeter and decimeter ranges. Several dozen stars located near the ecliptic and several nearby solar-type stars were studied. Several stars were also observed in the optical range using the 6-meter BTA reflector. None of the studied stars showed an excess of radiation flux over noise.

• The search for Dyson spheres, that is, hypothetical astroengineering structures supposedly built by extraterrestrial civilizations near their stars, is being conducted at the Astrospace Center of the Lebedev Physical Institute under the guidance of Academician N. S. Kardashev. It is assumed that these spheres absorb most of the energy of the star and re-emit it in the infrared, submillimeter and millimeter ranges, depending on the temperature of the structures. Such sources should have spectra close to the spectrum of a black body with effective temperature from 3 to 300 K.

Project estimates

The blatant lack of results after several decades of hard work is forcing supporters of the active search for extraterrestrial intelligence to find answers to difficult questions. One of the obvious shortcomings of the project can be called the fact that the search is only on certain frequencies of the radio range. There are suggestions that other civilizations use laser signals instead of radio signals. Modern optical communication devices operate on FSO (Free Space Optics) technology.

Another disadvantage, obviously, may be the wrong choice of radio bands. Extraterrestrial civilizations, if they exist, can use the most different methods compression. It may well be that, listening to compressed messages, which are also distributed over several frequency ranges, you can only hear “white noise”.

In his book The Physics of the Impossible, Dr. Michio Kaku reiterates the optimistic statements: “Given the rapid progress of the SETI program and the discovery of more extrasolar planets, contact with extraterrestrial life<…>could happen as early as this century.”

Criticism

At the same time, many criticize the project not only for the lack of thoughtfulness of search methods, but also for the fundamental ideas themselves. For example, Peter Schenkel, while remaining a proponent of the SETI projects, wrote that “In light of recent advances, we have become more insightful, and the best course of action seems to be to calm down the overexcitation and pragmatically consider the facts ... We must calmly admit that early assumptions about existence may be millions, hundreds of thousands or tens of thousands of advanced extraterrestrial civilizations in our galaxy are no longer reliable.”

There is an opinion that the SETI project can carry a serious danger. It is assumed that a highly developed alien civilization can use radio signals as an information weapon or means of its own distribution.

see also

Notes

1. Article in TIME Magazine "Earth-like Planets May Be Less Common than We Think" By Michael D. Lemonick Read more: http://www.time.com/time/health/article/0,8599,2095436,00.html #ixzz2BdEzZvI9
2. Cocconi G., Morrison P. Searching for interstellar communications // Nature. 1959 Vol. 184. P. 844-846.