The discovery of seven new exoplanets in the Trappist-1 system , 40 light years from Earth, announced by NASA scientists and published in the journal Nature , has brought to the table the possibility of the existence of life beyond our own planet. However, the geologist Jesús Martínez Frías, director of the Spanish Network of Planetology and Astrobiology, believes that we must be cautious before anticipating the possibility of the existence of extraterrestrial life.
“We must not confuse habitability with existence of life,” explains Martínez Frías. “Habitability consists of a planet having the necessary conditions to be habitable in a broad concept, from the most unique microorganisms to beings similar to us”, clarifies this expert. In his opinion, the fact that a planet can be habitable “does not mean that it will have life.”
Martínez Frías advocates not speculating on the possibility of existence of life on the recently discovered planets until there is palpable evidence. “The universe is immense and it would be absurd to think that we are alone, but it is true that, so far, we do not have any proof of the existence of life anywhere other than the Earth”, defends this geologist and director of the course on Planetology and Astrobiology from the Official College of Geologists (ICOG).
Existence of biomarkers
To corroborate the existence of life on the new planets or on any other celestial body, it is necessary, says Martínez Frías, to pay attention to the existence of biomarkers. “We have to be very restrictive with the term ‘biomarker’ and use it exclusively for what is clearly and unequivocally related to life,” he emphasizes. Martínez Frías considers that the existence of water on a planet is an environmental geomarker, “but by no means a biomarker, because it is not an organic compound related to the metabolic activity of an organism.”
However, this expert affirms that for a planet to contain life, it must “be alive” from the geological point of view. This geological vitality of a planetary body is, in his opinion, what causes that places where life can emerge or develop are constantly being created, destroyed and modified.
Definition of planet
Martínez Frías also advocates adopting a broader concept of the planet than is currently used, taking into account geological criteria over and above the dynamic relationships between different bodies. ” The planetary diversity is enormous and we should not classify typologies based on what we have in the Solar System,” he points out. “Perhaps we simply do not need a definition of a planet, because the variety of objects with these characteristics is such that it would escape our conception,” he concludes.
Source: Illustrious Official College of Geologists (ICOG)
