Is the day coming when intelligent beings will be found outside the earth?
Amnon Jaconte
The accused was sitting on a hard wooden bench dressed in the clothes of a monk. The traces of seven years in prison were visible on his washed-out face. "This is the last chance," said the father of the court, "do you repent of your apostasy?"
The accused shook his head in the negative. The judges consulted briefly among themselves, and the father of the court declared: "Giordano Bruno, by virtue of the authority given to us by the Holy Inquisition, we condemn your body to be burned and your soul to be spit in the purifying fire."
Bruno was not moved. He looked directly at his judges and said: "You pass my sentence out of a greater fear than I feel in the face of death."
A few days later, in the middle of February 1600, Giordano Bruno was put on the stake in the Campo di Fiori in the center of Rome. Fear did not die with him. Nor the scientific curiosity that Bruno represented. Both of them accompanied humanity in the course of the next 400 years, and to a large extent also caused that every step on the way to understanding space and what we do in it was accompanied by the question: Is there anyone out there similar to us?
Bruno, for his part, died when he was sure that the answer was positive. He never saw evidence of extraterrestrial intelligent life, but logically deduced its existence. A few decades earlier, another researcher, Nicolaus Copernicus, proposed that the sun does not revolve around the earth, but on the contrary, the earth and other stars move around the sun. The church was then in an era of relative liberality and hardly bothered to revolt, what's more, the publisher, Andreas Osiander, knew how to write in his introduction that "the hypothesis about the stationary sun was only intended to simplify the astronomical calculations", and reiterated in various ways that the earth was and remained the spiritual center of The universe is the exclusive object of God's attention.
Bruno appealed precisely this statement. Following Copernicus' hypothesis, the tiny scientific community established the notion that not only does the earth and other stars move around the sun, but that the solar system is not the only one in the universe. The stars of the Sabbath, for example, argued Bruno, are nothing but suns. Why then not assume that several planets, similar to the Earth, move around them? And if this is the case, there are many chances that conditions prevail there - water, light, vegetation and the like - that allowed the formation of intelligent life.
The idea that intelligent life does exist on other worlds was not a novelty. Many good people preceded Bruno in this, among them the Roman poet of the first century BC, Lucretius, who asked in one of his works (translation: Shlomo Dickman):
"Can you doubt anymore that there are worlds like our country in other places? Human seed like our seed, animals like ours?"
And he also explains the reason for this assumption: "You will not find in the whole of nature a single form that will grow alone of its kind"
However, none of all the thinkers and poets who raised the possibility of the existence of extraterrestrial life dared to draw from this the conclusion that Bruno made sure to spread in the open air: if there are indeed intelligent beings in other star systems, is it conceivable that God denied them the grace of revelation? And in such a case, is it possible to avoid the assertion that Jesus' revelation to humans was not such an unprecedented and unique event for our world?
The shockwaves that Bruno sent through the religious system lasted until the end of the 17th century. They made the church reconsider its liberal position and change its approach to the entire Copernican doctrine. In 1633, another researcher, Galileo Galilei, was forced to declare that he "denies, blasphemes and despises" Copernicus' theory. About 30 years later, Pope Alexander VII included in the list of books forbidden to be read "all books that maintain that the earth moves around the sun".
A visit to Roswell
All preventive measures did not help, as we know. The idea of the existence of intelligent life outside the earth continued to exist due to the power of two impulses - fear and curiosity. Space creatures were used for social criticism in the works of philosophers such as Voltaire, entertained the readers of science fiction books and also supported eccentrics and scientists themselves like Erich von Daniken, who tried to attribute incomprehensible phenomena in the geography and history of the earth to the visits of intelligent beings in the distant past.
Sometimes things got out of control, such as on October 30, '38, the day when the actor Orson Welles broadcast a radio drama, which was based on the book by H.G. Wales "War of the Worlds". Among other things, staged news flashes about the Martian invasion of New Jersey were incorporated into the plot. The combination of the talents of the two Welshmen, writer and performer, was so compelling that many people abandoned their homes and fled in panic to hiding places.
Intelligent beings from space, "extraterrestrials", as they were called in Hebrew, became the main representatives of the existence outside the earth. It is difficult to explain to the average newspaper reader the difference between a meteorite and an asteroid and between a white dwarf and a black hole, but it is easy to make him imagine an intelligent being that is different from us and at the same time similar, friendly or hostile, charming or repulsive, all according to the expectations and attitudes of the observer.
Surveys conducted in the fifties and sixties of the 20th century revealed that about 70 percent of the respondents believed in the existence of intelligent beings on other planets, and a little more than half of them were convinced that expeditions of such beings visited and still visit the earth. Allegedly, evidence was also found for this: mysterious circles harvested in wheat fields, charred dirt patches, deep excavations created overnight, dead animals and people who disappeared and returned without remembering what happened to them.
In some cases, the guests from space left behind even more complex mysteries. The most famous of them was born on the night between July 4 and 5, 47 near the town of Roswell in the state of New Mexico, United States. Some of the town's residents actually noticed a glow that crashed not far from their homes. They rushed there and found, according to them, fragments of an aircraft made of unidentified metal and several strange-looking bodies: small in stature, with pumpkin-like heads and eyes as round as coins.
A unit of the American Air Force arrived at the scene, closed the area to the curious and collected the fragments and the bodies. Three days later, the spokesman for the base located near the town announced that "a flying saucer was found near Roswell", and even stated that its remains were flown to the corps headquarters. A day later, the Air Force announced that the source of the news was a mistake and that it was parts that fell from a balloon that was making meteorological measurements. At the same time, the corps representatives were forbidden to discuss the issue on the grounds that the bullet took part in a secret experiment.
Towards the end of the 20th century, most of those involved in the incident were 70 years old or older. Some of them felt released from the obligation of secrecy and began to publish details about the case. The press got hold of a film that was allegedly taken during an autopsy performed on one of the bodies. The film was soon discovered to be heavy, but the evidence that dealt with fragments of strange metal and small corpses kept piling up from different directions. The most convincing of them is that of Air Force Colonel Philip Corso, who published a book in 97 called "The Day After Roswell". He said that he saw with his own eyes the body of one of the aliens, and even served in the unit whose job it was to decipher the technology found in the crashed spaceship and try to integrate it
in scientific research in the United States. According to him, this is why the United States was able to relatively quickly develop night vision devices based on heat, optical fibers, printed circuits and more in the XNUMXs and XNUMXs.
Nature's great deception
Cases like the one that happened near Roswell convince and even excite the general public, but not the scientists. Some of them tend to bypass the question of the existence of intelligent life outside the earth and some prefer to have only a passive activity on this issue, such as radio transmissions into space in the hope that some intelligent culture will receive them, or tracking by radio-telescopic means after signals coming from space.
A book published in 1999, "Journey to Reason" by the astrophysicist Prof. Hagai Netzer and the science writer Ami Ben-Best, laments the minor role that science has chosen to play in this field. After a systematic analysis of the possibility (actual, according to the authors) of the existence of intelligent life outside the earth, and a review of the (relatively little) effort made in this direction by the scientific community, Netzer and Ben-Best conclude: "The scientific approach to the study of these phenomena is difficult to define. In the last decades, the research in this field, at least the open research, is fading away. There are almost no experimental tests of UFO reports, certainly not by researchers from well-known academic institutions. In the scientific community in the world there is a large majority for those who believe that life in other worlds is absolutely possible. Why don't those researchers take one more step, and examine in a thorough manner the implications implied by that accepted assumption according to which interstellar journeys of intelligent beings have been or may be being conducted across the galaxy?"
Such a step was actually taken, and even a few rooms away from Prof. Netzer's room, in the Kaplan building at Tel Aviv University. Prof. Zvi Maza delves into the astronomical aspect of the question of intelligent life in the universe through observations. The conditions under which such life may exist are clear: "When it's too hot, the molecules break down, and when it's cold - the chemistry between them doesn't work or works too slowly. If we go one step further and assume that the creation of life requires water in a liquid state, then the necessary environment is one in which a temperature between
Zero to one hundred degrees Celsius".
Where in the universe can such an environment be found?
"Close to the sun, of course. Not necessarily our sun, but any star that emits energy similar to it. In our galaxy alone there are about one hundred billion suns. All but one or two of the four thousand stars visible on a dark night are suns. This is the greatest deception of nature: the stars of the Sabbath, the suns, look like the planets, Saturn for example. The temperature on these Saturn planets reaches thousands of degrees Celsius, so there is no chance of finding life on them. In the space around them there is also no chance, because of the cold. That's why we have to look for a planet that revolves around such a sun and has the right temperature for life."
dance in space
Maza's starting point is therefore exactly the one that brought Giordano Bruno his bitter end 400 years earlier: he examines suns in our galaxy and in other galaxies and tries to identify if planets exist around them. "Discovering a planet around another sun is a difficult technical problem. To illustrate this, suppose we are standing at the top of the Azrieli Tower and somehow overcome the curvature of the Earth so that we see the tip of the Eiffel Tower, at the top of which a XNUMX-watt spotlight is lit. But it is not the spotlight that interests us, but rather a small firefly swimming around it. Obviously, this is difficult, both due to the distance and due to the light intensity of the spotlight.
"For this reason, astronomers were unable to detect planets around suns for many years, until in the eighties of the 20th century, a technology was developed that made it possible to discover planets in an indirect way: each holiday planet around the sun exerts on it one or another degree of gravitational force, which also causes the sun to move a little. This is how the sun and its planet perform a kind of dance in space, with mutual gravity taking the place of holding hands. Naturally, the range of movement of the sun, which has a heavy mass, is much smaller than the movement of the star, but in any case where a small, cyclical movement of the sun is observed, it can be assumed that there is also a planet in its vicinity."
In the early nineties, Maza was a member of a research team based at Harvard University that found the first candidate in history to be a planet moving around a distant sun. However, even before it was finally determined whether it was indeed a planet (the matter is under investigation to this day), another Swiss team discovered that Saturn's planet Pegasus (the flying horse), 51 which is about 30 light years from Earth, moves in space in a circle, in cycles of four days. From this it was determined, by way of the straw, that there is a planet in its vicinity. Three months later, another American team discovered a similar phenomenon in the star Virginis (Virgo group) 70 and star No. 47 in the Ursa Major group (the Great Bear).
Life forms that do not occur to us
What does life look like in those stars where its existence can be assumed? This depends largely on the environment. It is assumed that some characteristics, such as organs of sight, hearing, nutrition and reproduction, will be common to all life forms, but their location and design will not necessarily be similar to those familiar to us. For the sake of illustration, let's imagine two planets whose existence can be tapped from the movement of some Saturn planet. One is relatively small and the other is very large.
In the small star, the gravity is about one tenth of that on Earth. During most of the day, the star is hidden behind its giant brother, so there is real light only during the sunrise and sunset of the local sun, the star of the Sabbath. During the rest of the day the sky is dark and very cold. If that is not enough, then the weak gravity existing on top of the small star means that gases do not "stick" to it and the air is thin. The life forms on the planet have obviously adapted to these living conditions. They grow tall, grow curling limbs to protect against the cold and have developed large, sensitive eyes to see in the dark. In the thin atmosphere the lungs are not of much use, and they breathe through a branched system of gills. The vegetation is also different, apparently. In the little sunlight, the chlorophyll we are familiar with cannot properly carry out the photosynthesis process, and its place is taken by another type of chlorophyll, which colors the plants purple.
In the big star the situation is completely different. Gravity is ten times stronger than on Earth, and it "fastens" the air, water, vegetation and animals to the surface of the planet. As a result, the atmosphere is compressed and suffocating and the ground is waterlogged and muddy. In such conditions, of an always hazy atmosphere, there is no point in developing a sense of sight and the creatures living on the surface of the great star orient themselves in the environment by receiving the echoes of sound waves, like the bats on Earth. The sheer pressure causes them to become flat and packed with armor. Their movement is very slow, to prevent overheating, and they are equipped with paddle-like limbs, to move forward in the muddy spaces. A slit-like mouth allows them to scoop up the moist soil and filter out the edible microorganisms.
With all due respect to the creative imagination invested in these speculations, their scientific and logical validity is questionable. As long as we try to describe the forms of life in other worlds according to what we know from what is found on Earth, there is a reasonable chance that we will miss other forms of life, which did not occur to us. When we describe the existence of "life" we use the tests that exist on Earth, according to which a living entity is the one that uses energy in a regular way, its body has clear boundaries and is able to reproduce. Even on Earth the definition is not valid in all cases: the flame of a candle has limits, it consumes energy and is capable of reproduction. Is she a living being? A mule, on the other hand, a cross between a donkey and a mare, does not
Ability to breed. Is he not alive?
A hint of the possibilities of life that we never thought of is sent to us from time to time in the form of chips of silicon (iron) found on asteroids when they are composited with other elements, creating materials that are able to survive and even thrive in the vacuum and the deadly radiation in space. Why not assume that in some corner of the universe, not necessarily on a planet close to the sun, a colony of silicon creatures thrives and sustains intelligent life? Why not assume that extraterrestrials can be made of gases (one of the most common building materials in the universe) and exist in our environment and even pass through our bodies?
Our own mature civilizations
The assumption underlying the big star and small star model, as if the environment shapes life forms, is also a legacy of life on Earth. There is no reason not to assume that other environments do not have such an effect on their inhabitants or that a civilization more developed than ours was able to shape itself independently of environmental conditions.
"Since our sun is five billion years old, and there are much older suns in the universe, it is possible that the civilizations there, if there are any, are much older than ours," speculates Prof. Maza. "If we look at what has happened to technology on Earth in the last hundred years, one can only guess what a civilization that is one hundred thousand years older than us has achieved, and one hundred thousand years is an astronomical benchmark."
Zvi Maza is fully aware of the limitations of his observations and the limitations of astronomy in general: "Many scientists have tried their hand at building theories about the nature and way of formation of our planetary system. Before the discoveries of the new planets, there was only one example - our solar system. The new discoveries open the door to new concepts. This is similar to someone who lives all his life in a closed room and has a flower pot on the basis of which he develops a theory in theology. If he opens the window to a crevice, his botanical understanding will change completely. And that's actually what astronomers do, they open a small hole in the dark window and try to take in as much as possible about the world through it."
