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Science

The search for extraterrestrial life

The ultimate human adventure 

Published in GralsWelt 52/2009

Half a millennium ago, the great seafarers were about to explore the world. They found unknown islands, discovered new continents and encountered foreign cultures.

The ultimate adventure back then was the encounter with an exotic high culture, such as that found in B. the English navigator William Adams (1564-1620) experienced. He ran aground with a Dutch ship on the Japanese coast. He became advisor to the most important Japanese prince and was the only foreigner to be raised to the rank of samurai. His life in Japan, his experiences with a completely foreign culture and its manners and customs, his learning of a different language, was probably the greatest adventure that a travel-loving seafarer could encounter at that time.

"If you put three grains of sand in a huge cathedral, the cathedral is more densely filled with grains of sand than space is filled with stars."    James Jeans (1877-1946).

And today?
The ultimate adventure, the unsurpassable exotic experience, would be an encounter with an alien civilization. Such a meeting with us alien intelligences has often been depicted in science fiction and films. Does such an expansion of our knowledge seem possible?
Opinions went and diverged.

Copernicus and Bruno
In antiquity as in the Middle Ages, the geocentric view of the world dominated Claudius Ptolemy (approx. 100 - 160), which saw the earth as the center of the world, around which everything revolves.

Then took over Nicolaus Copernicus (1473-1543) an actually very old one, already from Aristarchus of Samos (c. 310-230 BC) expressed the opinion that the earth moves around the sun. However, Copernicus did not publish his "Six books on the orbits of the heavenly bodies" until the year he died; because as a cleric, he foresaw the horror to be expected in the (Protestant, Catholic, Orthodox) churches.

The heliocentric worldview of the Copernicus was theological explosive of the first order! Unlike in the Bible, the earth no longer stands still, it circles around the sun. Also recognized as an incontestable authority in the Christian West for centuries Aristotle is finally being questioned! (See. "The most powerful invention in world history", Under" History ").

The effect of the new theory, which should revolutionize the astronomical worldview and initiate the "Copernican turn", was initially limited.

One of the few who recognized the revolutionary importance of the Copernican view of the world was the Italian philosopher Giordano Bruno (1548-1600). This one wasn't happy with that Copernicus had moved the earth from the center of the world and made it a satellite of the sun. He spoke of an infinitely large universe and thus totally overwhelmed the comprehension of his contemporaries. In the fixed stars in the sky he saw suns like our sun, surrounded by planets like our earth, which are inhabited by people like us. His ideas not only shattered the geocentric worldview that had prevailed for many centuries, but also shook fundamental theological teachings.

the end Brunos The worldview also gave rise to a question that could not be answered by anyone: How is the uniqueness of Jesus' mission to be understood, in an endless universe, with innumerable worlds inhabited by people who are similar to us and who are probably also in need of salvation?

The Catholic Church left Bruno After eight years of imprisonment because of his heretical ideas - which anticipated large parts of our worldview today - burned in Rome in 1600. He is fully rehabilitated by the Church (unlike Galileo) not until today!

The still open question about other inhabited worlds was for Giordano Bruno answered philosophically: Where there are opportunities for life, there will also be life! A thought already expressed by ancient philosophers: (See box).

“The world must be unique. There cannot be several worlds. "         Aristotle (384-322 BC).

“There are innumerable worlds, both such as ours and others. Since the number of atoms is infinite ... they are carried far out into space. Since the atoms, from which a world can basically be created or composed, are not used up in any single world and in any finite number of worlds ... nothing speaks against an infinite number of worlds ... We have to accept that there are living beings on all worlds, Plants and other things as we see them in our world. "                      Epicurus (341-271 BC).

“He is worshiped not only by one but by innumerable worlds;
not from a single earth, a single world, but from a thousand, a thousand, I say: an infinity of worlds. " Giordano Bruno (1548-1600).

“What remains for the human being is consciousnessbe that he is alone in the soulless emptiness of the universe that produced him. "   Jacques Monod (1910-1976).

“According to current evidence, where the initial conditions are right and billions of years are available for evolution, life should arise. The fact that life begins on suitable planets seems to be part of the chemistry of the universe. "
Carl Sagan (1934-1996).

Kant and Laplace
After this Giordano Bruno had propagated his fantastic idea of the infinite universe, almost two centuries passed before the first tentative, scientific answers to the question of other habitable planets appeared possible.

Immanuel Kant (1724-1804) published his “General Natural History and Theory of Heaven” in 1755 (cf. “The world description of the bold Kant", Under" Remembrance Days "). According to this, our solar system with its planets has condensed from a huge nebula. This "nebular hypothesis" was 1798 by Pierre Simon Laplace (1749-1827) improved. Today it appears in textbooks as the “Kant-Laplace hypothesis”.

This hypothesis provides a preliminary answer to the question of even more intelligent life in space: Suns - like our central star - are formed from masses of gas and dust and surround themselves with planets. So one can assume that many or all of the suns in space are surrounded by planets, some of which should be habitable. Hence, it's probably not just us!

Then in the 19th century many astronomers questioned the habitability of other planets. Only a few believed to find evidence of extraterrestrial intelligent life in our solar system in the controversial "Mars channels".

The catastrophe hypothesis
For a century, the nebular hypothesis was the most important scientific explanation for the formation of our solar system. But it had shortcomings that became more apparent as the observation material increased. So other theories had to be looked for.
At the beginning of the 20th century, the "tide hypothesis" or "catastrophe hypothesis" appeared, which was among others by Sir James Jeans (1877-1946) was represented. Here one assumes a near collision of two suns. Masses were extracted from our sun and the other, which condense to form planets.
Since such close encounters between two suns are extremely rare, there could only be a few planetary systems. Our earth would then be one of the very rare, perhaps the only inhabited planet in immeasurable space.

The turbulence theory
The catastrophe hypothesis did not hold up to more precise calculations, and one had to return to a primordial nebula as the origin of the solar system. Karl Friedrich von Weizsäcker (1912-2007), whom I still knew personally, published an improved theory in 1946, which assumes eddies or turbulence in the dusty masses of the primeval mist. His theory was expanded several times, but questions remained unanswered.
Today, a huge gas and dust cloud is generally considered to be the origin of our sun and its planets. If all suns were created in the appropriate way, then many of them should also be surrounded by planets.

As far as we know today, there are around 100 billion galaxies in the observable universe, each of which consists on average of around 100 billion suns. That would be all in all 10 trillion suns. If only every millionth sun had a habitable planet, there would be 10 quadrillion potential places to live.

Several planets of distant suns, so-called "exoplanets", have already been detected. However, it is mainly uninhabitable giant planets that can be identified. So far only a single exoplanet, somewhat similar to our Earth, has been discovered. But astronomical observation technology is making progress, and we can hope that in the not too distant future more planets will be found that offer an earth-like environment.

The astronomy professor Geoffrey Marcy from Berkeley University, who discovered about 130 of the more than 200 known extrasolar planets, is optimistic: 

“In our research we found that ten percent of all stars have companions. So of the 300 billion stars in the Milky Way galaxy there could be 30 billion planets, including many Earth-like ... In ten years we will discover a blue planet. " (7, p. 32).

Could some of these “blue planets” be inhabited? Maybe with different colored plants? If the light of the sun there is more greenish, instead of the reddish incidence of light on earth, any forests there could appear red.

Is there a chance of receiving radio signals from inhabited exoplanets that suggest highly developed intelligences? Scientists are trying to establish such contacts as part of the SETI (Search for Extraterrestrial Intelligence) project. (11).
As said Carl Sagan (1934-1996): "If we are alone in the universe, that would be a terrible waste of space."

The time window
Our universe is maybe 14 billion years old. But as far as we know today, life has only been possible for a comparatively short period of time, as the prerequisites for it had to be created first.

After the “Big Bang” there was only hydrogen and helium in the universe. 100 or 200 million years after the Big Bang, these gas masses condensed into giant primordial suns, many times heavier than our sun.

In this first generation of stars, elements that are indispensable for life, such as nitrogen, oxygen, carbon, and iron as the heaviest element of the first time, were created through nuclear fusion. When these giant suns were burned out and exploded, very heavy elements such as uranium and thorium were formed in a rapid fusion process.

Now about fifty more elements, heavier than iron, were missing. These were formed in a second generation of decidedly smaller stars that were much longer-lived; because the bigger the sun, the faster it consumes its nuclear fuel.

Our solar system only belongs to the third generation. Previously, stars of the second generation also had to explode and release the elements they formed into space. Only then could gas and dust clouds condense into solar or planetary systems, which have all the prerequisites necessary for life.

Our planetary system was formed about 5 billion years ago and about 10 billion years after the Big Bang. According to current ideas, there are hardly any significantly older suns with habitable planets.

Where can life arise?
Under the given circumstances on our earth, organic life has developed in the basically known way over the course of three billion years.
Would life also be possible under other conditions?

Not only science fiction authors but even scientists toy with the idea that there could be life under conditions that are totally strange to us; z. B. on Jupiter's moons or even in the dense atmosphere of Jupiter. One can also speculate about whether organisms based on silicon (instead of carbon) would be possible; with a fundamentally different energy supply and possibly at a different temperature level.

Some esotericists believe that the spiritual can create animated bodies, i.e. life, everywhere, even in an environment that is completely different from the earth. But these are speculations without a sustainable scientific foundation.

Since we cannot know better, we have no choice but to start our search for extraterrestrial life from the conditions on our earth.

In order for a planet with living beings to arise, a number of requirements would have to be met; so many that not a few scientists, such as B. Harald Lesch, doubt that there will be a second planet with highly developed life forms:

· The central star of a habitable planetary system must not be much larger or smaller than our sun. If the central star is too big, it burns out too quickly. If it is too small, its “life zone”, the liquid-water zone, would be too narrow.
· The planet must be made of solid material and about the size of the earth. Planets that are too large, such as Jupiter or Saturn, collect too many gases and do not have a solid surface. Planets that are too small, like Mars, cannot hold a sufficiently dense atmosphere long enough.
· The planet must have sufficient water and its orbit must be within the liquid-water zone. For a uniform climate, this path can only be slightly elliptical. As we will read later, the frequently heard claim that the earth is "exactly at the right distance from the sun" is not without controversy.
· A moon that is not too small is required to stabilize the axis of rotation. Otherwise, the planet's axis of rotation could tilt over and over again every million years. The associated sudden climatic fluctuations would make life difficult or even impossible.
· During the billions of years that life needs for its development, there must be no supernova explosion within about 30 to 50 light years that could extinguish all life.
· In the planetary system, large planets like Jupiter are required. These must collect enough small and micro planets (asteroids) as remnants of planet formation, or comets. Otherwise z. For example, our earth is exposed to an ongoing bombardment of planetoids and comets, which can cause enormous damage.
· A magnetic field is required that deflects dangerous particle radiation - the solar wind.
· Volcanism and plate tectonics have to pile up mountains. Otherwise there would only be one planet covered with water everywhere. The uniform living conditions in the sea offer too little incentive for evolution.
· According to today's doctrine, numerous evolutionist "coincidences" were necessary to form a more highly developed life. Because life could have stopped at the level of bacteria and algae.
· Whether major disasters were necessary for human development is controversial. Without the demise of the dinosaurs (through an impact?), Probably neither the mammals nor humans would have been able to prevail.

Given this multitude of necessary prerequisites, there are three basic philosophical viewpoints about the origin of life:

1. It was a "miracle". A miracle is to be understood here as a (religious) event that moves outside of the laws of physics.
2. It was an extremely unlikely coincidence.
3. It was a result of physical and chemical laws to be expected under suitable conditions. (2, p. 35).

Many scientists, such as B. the French biochemist and Nobel Prize winner Jacques Monod (see box), are of the opinion that within the framework of the laws of nature known to us, there is only room for chance.

Personally, I prefer point 3. For this I refer to the conditions on our earth. Life can be found almost everywhere here: in the deep depths of the oceans, in tropical deserts, in the mountains to over the snow line, in hot springs and arctic latitudes. Wherever such unusual conditions make life possible, there are also - sometimes extremely adapted - ways of life.

The Gaia Hypothesis
It has long been known that life changes the conditions on our planet. For example, the oxygen in the air comes from the assimilation of plants. In addition, life seems to have a purposeful effect and create life-friendly conditions on our planet:

Formulated in the early 1970s James Lovelock (born 1919) together with Lynn Margulins (born 1938) the "Gaia Hypothesis". This postulates

“That life on earth actively regulates the surface conditions in such a way that they are favorable for the ensemble of organisms that currently inhabits them. Initially, this idea ran counter to school wisdom that life had adapted to planetary conditions and that both had developed separately. We now know that both the original Gaia hypothesis and that school wisdom were wrong. The hypothesis developed into today's Gaia theory and school wisdom developed into geosystem science. " (4, p. 234).

In general, little is known that - how Lovelock notes - the sun is slowly getting hotter and emits around 25 percent more energy today than it did billions of years ago. In his opinion, our planet would have long since been barely habitable without Gaia's balancing work:

“Most textbooks and popular science television programs want us to believe that the earth happened to be born exactly the right distance from the sun, which is why the conditions on earth are just right for life. This pre-Gaia claim is wrong, because the heat of the sun was ideal for life for only a brief period in the history of the earth, and that was around two billion years ago. Before that it was too cold, and then it gradually got hotter and hotter. " (4, p. 71).
According to this, one can view “Gaia”, the totality of life on earth, like an organism that reacts flexibly to external influences and maintains life-friendly conditions.

Unfortunately, in our blind egoism, we are currently in the process of removing the ground from Gaia and thus sawing off the branch from which we are sitting! (See. "Gaia's revenge", Here under" Book reviews ").

The anthropic principle
From the first fractions of a second in the formation of the universe until today there have been innumerable events that had to take place in a very specific way so that beings could finally arise who reflect on their existence and their meaning.

This includes the extremely fine coordination of natural forces and natural constants. These are so meticulously balanced that scientists compare them to a pencil balanced on its tip. (See. "The big bang as proof of God", Under" Science ").

The anthropic principle, which z. B. recognizes very specific prerequisites without which we would not exist.

That weak anthropic principle considers it possible that there are any number of universes (“multiverses”), one of which (coincidentally) is such that it produces “observers” (thinking beings).

That strong anthropic principle recognizes that very specific conditions controlled the development of the universe in such a way that higher life could arise. A fundamentally different universe would have developed through only minimal deviations in one or the other natural constant (9).

Both varieties of the anthropic principle are not strictly scientific theories, since they can neither be proven nor refuted. Nor do they help us in the search for life on distant planets. Unless one tries to construct a proof of God from the anthropic principle and to deduce from it that the whole universe must be animated. But that would be philosophy, theology, natural theology, or esotericism, not natural science.

Aliens in the Bible?
There are quite a few Bible passages in which supernatural beings, angels, etc. appear, which are interpreted by some as aliens.
For example, a strange passage is Genesis 6: 1-4. UFO believers see this as evidence of visits by aliens to earth.
Ezekiel (Ezekiel) 1,4-28 is interpreted as an encounter with extraterrestrials of the "third kind", ie a personal encounter with making contact.
And Job (Job) 38 is even interpreted by clerics as an indication of extraterrestrial intelligences. (Cf. Arte documentation "The Extra-Terrestrial Part 1", broadcast on November 12, 2007):
“Where are their pillars sunk? Or who laid the cornerstone when all the morning stars shouted, as if all the sons of God were cheering? " (Job 38: 6-7). Here we are talking about a time before the creation of man, and it is the jubilant "sons of God" that give rise to speculation.

Are we alone in the Universe?
Over the centuries, mankind has been able to accumulate a great deal of knowledge about the universe: the origin, age, structure and even the future of the universe seem to be known in principle. The development of the stars with the planetary systems surrounding them has also been unraveled.

But what do we know about the inhabitants of other planets?
In our solar system, extraterrestrial life should, at best, only exist in the form of primitive creatures such as bacteria or algae.

And how and where do we meet "extraterrestrial intelligences", ET, aliens or whatever they are called in science fiction literature?
When it comes to the question of all astronomical questions, "Are there other thinking beings in the universe?", We are hardly further than ancient philosophers and feel in the dark.

If this question should be answered with “yes”, the next question follows: “Do we have a chance to get in contact with you?” Can we maybe even meet you personally? Or are all possibly inhabited planets in unreachable distance?
Nobody knows if these questions will ever be answered.

Literature:
(1) Breuer Reinhard, Das anthropische Prinzip, Meyster, Munich 1981.
(2) Davies Paul, Are we alone in the universe ?, Heyne, Munich 1995.
(3) Hagl Siegfried, If it wasn't a miracle, Verlag der Graal Message Foundation, Stuttgart, 2002.
(4) Lovelock James, Gaias Rache, Ullstein, Berlin, 2007.
(5) Lesch Harald / Müller Jörn, Big Bang second act, Goldmann, Munich, 2005.
(6) Littrow Jos. Joh. V./Stumpf Karl, The Miracles of Heaven, Ferd. Dümmler, Bonn, 1969.
(7) PM, October 2006.
(8) Wabbel Tobias Daniel, SETI - the search for the extraterrestrial, beustverlag, Munich, 2002.
(9) http://www.cip.physik.uni-muenchen.de/+zimmermann/dl/anthrprinz.html.
(10) http://www.klawi.de/anthr.p.htm#Anker1anthr.p.
(11) http://de.wikipedia.org/wiki/SETI.

Attachment:
The Fermi Paradox       

In 1950, Enrico Fermi, Edward Teller, Emil Konopinski and Herbert York discussed alleged UFO sightings and a cartoon from The New Yorker magazine about aliens on their way to lunch.
Finally Fermi asked: “Where is everybody?” Why are there no other space-dwelling spaceships or other traces of extraterrestrial technology to be seen? Because of the age of the universe and its large number of stars, life should also be spread outside the earth; assuming the origin of life on earth would not be an extraordinary accident.
There are different answers to this question, but Teller supposedly concluded "The most likely cause is that highly developed societies self-destruct before they are sufficiently advanced." This self-destruction should take place regularly within 100 years of the invention of nuclear weapons. The 100th anniversary of the Hiroshima bomb is 2045! (Source: Wikipedia).
Interestingly, for these scientists (and most of them still do) it was a matter of course that a highly developed civilization must follow a path corresponding to the one we have followed on earth. Apparently there is no other way of thinking.
Would it be B. Is it possible for a completely different "humanity" to follow a path that is not only mind-controlled but more sensation-guided, natural? In harmonious cooperation with beings (natural beings, devas) who would warn of wrong ways like nuclear energy?