A million years of searching have turned up nothing but according to the Drake formula there is something to look forward to

The millions of personal computers around the world harnessed to detect life signals from space crossed last week the limit indicating one million years of processing

The radio telescope near the city of Arecibo in Puerto Rico. The signals received by its antenna are recorded and sent to SETI for processing. A few days ago a project crossed SETI @ Home The milestone that marks a million years of processing. This means that home computers around the world have collectively contributed a million years of work to the search for life signals from outer space.

The pioneering project started in 1999 at the initiative of the SETI Extraterrestrial Intelligence association. the Search for The goal is to locate signs that indicate a transmission originating from a foreign intelligence. The working assumption is that if there is indeed, somewhere in space, a planet on which life and an intelligent culture with technological capabilities have developed, then there is a chance to discover it and maybe even make contact with it.

SETI personnel record the signals received from space at the site of the largest radio telescope in the world (diameter 305 meters), near the city of Arecibo in Puerto Rico, and from there the signals are sent for processing at the SETI offices in California. In their raw form, the resulting recordings contain a multitude of radio signals of various types at various strengths and frequencies. The goal of the researchers is to locate a signal originating from a distant civilization among all the recorded signals.

The problem is that space is full of electromagnetic noise: galaxies and giant gas clouds in space emit radio waves, and astronomical phenomena such as supernova explosions produce loud radio noise. In addition, many devices on Earth emit radio waves. The human-origin disturbances are particularly problematic: not only are they strong and close, but they are regular and have a fixed pattern and therefore may mislead. The assumption of the researchers is that the requested signal will indeed have an orderly pattern, indicating that it is the product of intelligence and not a natural phenomenon; But it must be established that its origin is distant and that it is not a local disorder.

To carefully scan through all the recorded signals, reject the interference and noise, and look for the real thing, a huge amount of data must be processed; An amount so large that the fastest supercomputers in use today would take many years to complete the processing. SETI therefore proposed an alternative solution: they divided the information into small pieces and asked the general public to help and donate processing time on their personal computers. The principle is simple. Millions of computers are connected to the Internet, and those who decide to help the project can download the SETI screen saver from their home site and donate computing time.

project SETI @ Home He is the first to implement the concept of distributed computing on the Internet on such a large scale. Over time, about 3.5 million volunteers joined it, a number that is above and beyond the most optimistic dreams of the project's creators (Israel, despite its size, is in the respectable 31st place in the list of countries, according to the number of processing units donated to the project; China, by comparison, is in the -29).

The massive mobilization for the project coincides with the wave of public interest in the subject of extraterrestrial life. However, scientific research in the field is limited: many scientists claim that they avoid engaging in the subject due to the lack of direct evidence and accepted research tools, and the funding for research in the field is extremely limited. Despite this, there are groups of scientists, such as the SETI people, who are ready to approach the subject and be pioneers when it comes to developing the necessary scientific tools and scientific methods.

At the basis of the organized scientific research on extraterrestrial intelligent life are the ideas of the American astronomer Dr. Frank Drake. In the early sixties, while working as a researcher at the National Radio Astronomy Laboratory in West Virginia, Dr. Drake formulated the formula (hence known as the Drake formula), which estimates the probability of the existence of advanced extraterrestrial civilizations, which can theoretically be located. It was a first attempt to illuminate the question with scientific light and quantitative tools.

Since many components of the Drake equation are unknown, it cannot accurately predict what the chances of the existence of intelligent life outside the earth are, but it points to the directions of research and the method that should be used to search for the answer.

The formula is a simple product of seven factors: fl * ne * fp * N = R * L * fc * fi Although it is formulated as an equation, it can be seen as a sequence of scientific questions.

First question: How many stars of the type suitable for forming life-supporting solar systems are formed each year (R)? Our sun is an example of a suitable star - not too big, not too small, one around which a planet like Earth can develop in orbit.

Second question: among the suitable stars, what is the percentage of stars around which planets will form (fp)? The assumption is that planets do not necessarily form around every star, even if it is suitable for this in its data.

Third question: What is the number of planets, in a given system, that have a suitable configuration for the formation of life (ne)? The planets must be at the right distance and have the composition that allows the basic life factors to join together and produce the first simple life forms. It should be noted that this is organic life, more or less as we know it. There may be completely different types of life, but we currently have no information that hints at their nature.

Fourth question: What is the percentage of planets, out of those that have the appropriate conditions, on which the process leading to the appearance of life (fl) will occur? It is not necessary that suitable conditions will indeed lead to the formation of life.

Fifth question: What is the percentage of planets that can be hypothesized to develop intelligent life (fi)? Most of the animals we know have not reached a level of intelligence that allows the development of a complex culture. There may be distant worlds teeming with life that are not intelligent enough to create a culture - a kind of giant jungle - as our world was before the development of human culture.

Sixth question: If intelligent cultures are created, what percentage of them will develop means of communication (fc)? In the absence of these means we will not be able to locate or communicate with these life forms from Earth. It is possible to assume that there are developed and diverse cultures that did not develop in the technological direction, and did not develop electromagnetic means of communication such as radio transmitters.

Seventh question: What is the length of time that the cultures that meet these conditions can persist in their transmissions; Or in other words: how long have these cultures existed (L). Many thinkers were asked the question, if an advanced technological culture is guaranteed a continuous existence, or if it is precisely the technological advance that will bring an end to these cultures. This is the most difficult variable to estimate.

After placing an appropriate value in each of the factors of the formula, the result is obtained, N, which is the number of civilizations, in the Milky Way galaxy, that have the ability to communicate through radio waves; The number of distant civilizations that we have a chance to locate.

Immediately after the publication of the Drake formula, various scientists began to try to adjust values ​​to the formula. Obviously, it is very difficult to estimate the value of some of the factors, so an effort is made to make an informed guess, by searching for the possible limit values. It is possible, for example, to say with certainty that all variables are greater than zero; After all, we know of at least one intelligent culture that developed in our galaxy. It is also possible to estimate today, following new discoveries in astronomy, the values ​​for the first three factors, related to the characteristics of planetary systems. The number of suitable stars formed each year is today estimated at about 10 stars per year. The formation of planets is estimated at 0.5, which means that around half of the suitable stars will form planets. In any suitable system, it is now generally accepted to estimate, there will be about two planets with the potential to create life. Also, various experiments have shown that, given suitable conditions, simple molecules join together to form the building blocks of life. It is acceptable, therefore, to attribute the value 1 (or 100%) to the variable that evaluates the chances of life forming given the appropriate conditions.

In the light of those discoveries, it seems that the hypothesis that our world is not the only home to life in the universe is getting stronger. There are other suns similar to ours. It has recently been proven that there are planets orbiting these suns. Some of them resembled, most likely, the Earth. And on them basic molecules will connect to the primary life forms.

Regarding the factors related to the development of a civilization from simple life forms, and its ability to develop communication technology, we have only estimates. At this point, the values ​​0.1 to 0.4 are acceptable for these variables. And regarding the duration of the existence of a technological culture, the estimates range widely. Different versions attribute to this variable a value of 100 years, 1,000 years, and some estimate even more.

It is interesting that when the marginal and approximate values ​​are placed in the formula, it becomes clear that the result N is roughly equal to the variable L, which indicates, as mentioned, the time of existence of a given civilization. Or in other words, the number of our intelligent neighbors in the galaxy is equal to the number of years that an advanced civilization, with technological means, can survive. Considering the recent events in our civilization, perhaps it is no wonder that so far no signs of life have been found in any of my computers .SETI@Home The author is an expert in information systems and a graduate of the philosophy department at Tel Aviv University