No one knows how life originated
There are fantasies who claim that life comes from space and
that therefore it should be of alien origin.
These folks are just shifting the problem a great many miles and do not provide any
solution aimed at the answer to the original question.
Dr. Frankenstein made a kind of robot out of tissue from various criminals and
he released lightning on the body. Its energy brought to life the dead organ assembly:
Frankenstein's monster.
Nice idea, but it is a pure fabrication.
We see something similar in the Golem from Prague. It is therefore a wonderful science fiction theme.
Louis Pasteur has seriously experimented to await spontaneous life in a pre-sterilized room.
Result: zero point zero.
An important side effect of his experiments was the awareness of hygiene.
Every effort has been made to obtain life from inanimate matter. All kinds of primordial
soup and its processing have been tried, but the recipe for life has still not been found.
The people have no assurance that they will ever be able to create life from inanimate matter.
Blood
A tip of the veil of the riddle about life is lifted in a bible passage which prohibits
the consumption of blood. LEVITICUS chapter 17 lines 10-14:
10 Each of the house of Israel and of the strangers who abide among them,
-- who eat any blood, against anyone who has eaten the blood,
-- I will turn my face and cut him off from among his people.
11 For the soul of the flesh is in the blood and
-- I have given it to you on the altar to make atonement for your souls,
-- for the blood makes atonement by means of the soul.
12 Therefore I said to the Israelites: "None of you shall eat blood.
-- Even the stranger who sojourns among you will not eat blood.
13 And every one of the Israelites and of the strangers that tarry among you,
-- who hunts game or poultry that may be eaten,
-- shall let pour out its blood and cover it with earth.
14 For as for the soul of all flesh the blood of it is its soul;
-- therefore I said to the Israelites, You shall not eat blood of any flesh,
-- for the soul of all flesh is the blood: whoever eats it, shall be cut off."
Apparently, the secret of life is hidden in the blood.
Of course, we know, that no human or animal can survive with too little blood.
For now, we only have one serious statement:
life was begotten by a super intelligence.
Is there alien life?
Is our civilization the only one in the universe? Or are there more, but then among exoplanets?
Many scholars like to reason as follows.
Exoplanets are planets outside our solar system that orbit a parent star. In principle,
life could have originated on many of those exoplanets, in whatever form.
A small fraction of it, but still in great numbers, may then be intelligent life with a civilization somewhat similar to that of humans.
Strictly speaking, this view is purely speculative.
This idea was born of the desire to be able to connect with alien life.
In 1950, nuclear scientist and Nobel laureate (1938) Enrico Fermi said:
"If there are so many of those alien civilizations, why don't we notice them at all? If we invented radio transmitters and sensitive receivers, radio telescopes, why couldn't exo-civilizations be able too?" That statement became known as the Fermi Paradox.
Since 1960, radio astronomers at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia have been trying to pick up on signs of exo-civilization. The enormous radio wavelength range extends from meters to kilometers. All conceivable radio waves can be received and recorded simultaneously. Many powerful computers analyze the gigantic signal supply, and suitable equipment tries to lift serious candidate signals above the noise.
Pulsars
For a moment it seemed that great success was being achieved. This is because radio signals were received from a well-defined spot in the sky with an incredibly tight regularity. Bingo, it was soon thought that the first pulsar had been discovered to which no exo-intelligence was linked. Too bad. Jocelyn Bell was the heroine.
Search for Extra-terrestrial Intelligence = SETI
Shortly before the turn of the millennium, there was a good idea to make the most of the many home computers on earth during their unused hours. The volunteers let a kind of screen saver do the work. Five billion interesting signals have been lifted from radio noise by millions of PC users worldwide during the SETI project for four years. After four years, only the most promising 200 of these were examined more closely. The rest remains unused due to a lack of sufficient radio telescopes, manpower and money. The two hundred selected signals came repeatedly from the same place in the sky and had a fixed frequency.
The closer the source was to a sun-like star, the more promising the signal.
Radio silence
Sadly, radio evidence of exo-intelligence stubbornly stayed away, even though there really should be plenty of suitable civilizations, including on planets like our Earth. And the technicians on earth have not been idle either. The observation quality and capacity was continuously increasing by leaps and bounds.
Why are we not receiving serious signals?
There are many explanations possible to explain the radio silence.
The first is very obvious: humans are truly unique in the universe.
Radio astronomy has only been practiced for 75 years on earth.
For example, if a signal was received from us 40 years ago at a civilization and it takes a year to send an appropriate response, the signal will be on the way for another 40 years. A possible answer will then take 80 years to arrive. Not a pleasant time for a conversation. The sender also recognizes this and therefore does not feel like exchanging information.
There may be enough high-ranking civilizations that don't even cross their minds, or are unique in the universe. Maybe only we are so curious. Or they are afraid: you never know what you will get.
When a signal is sent in all directions, looking along a straight line from the source, the signal becomes increasingly weaker, as it is smeared over an ever-larger imaginary sphere: the signal strength decreases with the square of the distance and then we are not even talking about possible damping on the road by some thin medium.
We do not know if our alleged distant brethren of high civilization have radio receiving equipment with adequate amplification.
Civilizations may have transmitted signals long before our radio telescope era and that they arrived later, but before our radio telescope era. We were simply too late with our technology.
Our solar system has been around for several billions of years.
If we are to believe Erich von Däniken, Earth has long been explored by space travelers as the most life-friendly planet in our solar system.