Revealing the properties of other worlds in our solar system, we gradually realize that the Earth is unique. Only our planet had liquid water on the surface; only we had a complex, multicellular life, the existence of which can be guessed by looking from orbit; only we had copious amounts of atmospheric oxygen. Other worlds may have underground oceans or evidence of past liquid water, perhaps even single-celled organisms. Of course, other solar systems may have worlds like Earth, with similar conditions for life to arise. But for life to exist, the existence of an earthly world is not necessary. Recent findings by scientists show that peace may not be needed at all. Perhaps life lies in the depths of interstellar space.
Signs of organic, life-giving molecules are found throughout space, including the largest star-forming region nearby: the Orion Nebula.
As far as we know, life only needs a few key ingredients. She needs:
- a complex molecule or a set of molecules, - able to encode information, - be a key driver of the body's activity
- and perform functions of collecting or storing energy and directing it to work, - at the same time be able to make copies of yourself and transfer the encoded information to the next generation.
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There are fine lines between living and non-living, which are not fully defined; bacteria enter, crystals come out, and viruses are still in question.
Formation and growth of a snowflake, a special configuration of an ice crystal. Although crystals have a molecular configuration that allows them to reproduce and copy themselves, they do not use energy or encode genetic information.
Why do we need a planet for life to appear? Ethan Siegel asks Medium.com. Of course, the aquatic environment provided by our oceans may be ideal for life, but the raw materials for it are found throughout the Universe. Supernova stars, neutron star collisions, mass ejections, hydrogen and helium burning all add to the periodic table. After a sufficient number of generations of stars, the universe was filled with all the necessary ingredients. Carbon, nitrogen, oxygen, calcium, phosphorus, potassium, sodium, sulfur, magnesium, chlorine - whatever life desires. These elements (and hydrogen) make up 99.5% of the human body.
The elements that make up the human body are necessary for life and are located in different places on the periodic table, but they are all born in processes associated with several types of stars in the Universe.
For these elements to stick together into an interesting organic configuration, an energy source is needed. Although we have a sun on Earth, the Milky Way galaxy alone contains hundreds of billions of stars and many sources of energy between stars. Neutron stars, white dwarfs, supernova remnants, protoplanets and protostars, nebulae and much more fill our Milky Way and all large galaxies. When we study the ejections of young stars in protoplanetary nebulae or gas clouds in the interstellar medium, we find complex molecules of all kinds. There are amino acids, sugars, aromatic hydrocarbons, and even exotic components like ethyl formate: an unusual molecule that gives raspberries their characteristic smell.
There is even evidence that there are Buckminsterfullerenes in space in the exploded remains of dead stars. But if we return to Earth, we find evidence of these organic materials in some not-so-organic places: inside meteors that fell from space to Earth. Here on Earth, there are 20 different amino acids that play a role in biological life processes. In theory, all amino acid molecules that make up proteins are identical in structure, with the exception of the R-group, which can consist of different atoms in different combinations. In terrestrial life processes, there are only 20 of these and practically all molecules have left-handed chirality. But inside the remains of asteroids, you can find more than 80 different amino acids, left and right chiralities in equal amounts.
Many amino acids not found in nature were found in the Murchison meteorite, which fell to Earth in Australia in the 20th century.
If we look at the simplest types of life that exists today, and look at when different and more complex types of life appeared on Earth, we will notice an interesting pattern: the amount of information encoded in the genome of an organism increases with increasing complexity. This makes sense, since mutations, copies, and redundancy can build up information within. But even if we take the least clogged genome, we will not only find that the information increases, but also that it does so logarithmically over time. If you go back in time, you will find that:
- 0.1 billion years ago, mammals had 6 x 109 base pairs.
- 0.5 billion years ago, fish had about 109 base pairs.
- 1 billion years ago, worms had 8 x 108 base pairs.
- 2.2 billion years ago, eukaryotes had 3 x 106 base pairs.
- 3.5 billion years ago, prokaryotes, the first known life forms, had 7 x 105 base pairs.
If you put it on a graph, something incredible can be discovered.
Either life began on Earth with a complexity of the order of 100,000 base pairs in the first organism, or life began billions of years ago in a much simpler form. This could have happened in a pre-existing world, the contents of which migrated into space and eventually ended up on Earth during a major panspermia event, which is definitely possible. And it could also happen deep in interstellar space, where the energies of galactic stars and cataclysms provided the environment for molecular assembly. Perhaps life was not always in the form of a cell, but in the form of a molecule that can collect energy in the environment, perform a function, reproduce and encode the information necessary for the survival of the produced molecule, completely.
A gas-rich nebula, driven into the interstellar medium by hot new stars formed in the central region. The earth may have formed in the same area, and this area may already be teeming with primitive life forms.
So if we want to understand the origin of life on Earth or life outside of Earth, we might not want to go to another world. The very secrets that open the key to life can be hidden in the most inconspicuous places: in the abyss of interstellar space. And if the answer really lies there, the ingredients for life will not only be found throughout the cosmos, but life itself can be everywhere. It remains only to figure out where to look.
If life really exists in interstellar space, virtually every world that forms in the universe today will store these primitive life forms until better times. And if he is lucky enough to provide future life with protection from radiation, find a source of energy and a friendly environment, evolution will be inevitable. Perhaps life on our planet owes its origin to the depths of interstellar space.
Ilya Khel