When we talk about the origin of life, there are always many doubts and theories. One of the best known and most accepted is that of chemical evolution, which proposes that life arose in the oceans of the early Earth. However, several researches suggest that the substances that contributed to the formation of the first life forms may have arrived on the planet, and not have been formed here. this is the call Cosmic Panspermia.
According to the Cosmic Panspermia theory, there were particles of life that would have fallen to Earth accompanied by comets and meteors. These particles would be like spores ready to germinate. It is believed that this hypothesis was initially proposed in the 5th century BC. a., in Greece, by Anaxagoras.
The theory was brought up again around 1879 by the works of Hermann von Helmholtz and William Thomson, who asserted the possibility of meteors serving as a means of transport for the life forms found in the space. Svante Arrhenius also contributed a lot to the theory. He suggested that the spores could be transported in space by the pressure of radiation emitted by stars.
Fred Hoyle, studying galaxies, found that it was possible for bacteria to travel through the universe. He observed that in space dust there were compounds of carbon and water, which reflected a certain spectrum of light, which was coincidentally the same as the bacteria reflected. When he exposed his theory in 1979, many researchers were skeptical of the theory.
Several works continued trying to confirm the Panspermia theory. Among them, Orguiel, Murchison and Allend stood out, who verified amino acids in meteorite cellars. These amino acids could have been brought to Earth and become components of the primitive oceans after their release. These meteors are believed to crash into water and release amino acids in the hydrolysis process.
Based on this theory, it could be that the entire galaxy has been bombarded with these life forms. or precursor substance, therefore, there is no reason why life cannot exist on other planets.
This theory still presents several doubts, such as: How did these micro-organisms travel through space, supporting all its adversities? Also, how were they formed elsewhere?
by Vanessa dos Santos
Graduated in Biology
Source: Brazil School - https://brasilescola.uol.com.br/biologia/panspermia-cosmica.htm