The landing of meteors 3.9 billion years ago has promoted life on earth

The bombing of the earth, which took place 4 billion years ago by a large meteorite in Kansas, was not enough to eradicate the entire primitive life on the planet and even motivate it, according to a new study. Colorado study at Boulder.

The evidence of the clash in the traces of the moon, meteorites and the planets of the planets drew a picture of violence in the solar system in the Hadean era from about 4.5 to 3 years ago. 8 billion years ago, especially the event of the cataclysm still known as the intense bombing occurred 3.9 billion years ago. Although many believe that the event has depleted the earth, the new study suggests that it only partially flows the earth's crust, microorganisms that can survive easily in underground environments. was insulated from the destruction.

Oleg Abramov, a researcher at the University of Colorado at Boulder, said: 'The new research results have pushed back the start of life on earth before this bombing at about 3.9 billion years. ago. It also opens up the possibility that life has flourished long before, 4.4 billion years ago, at a time when the first oceans began to form. '

An article on this topic was written by Abramov and geology science professor Stephen Mojzsis of the University of Colorado - Boulder, published in the May issue of Nature.

Due to the natural evidence of climate-related meteor attack and the stratigraphic plates overshadowed, researchers had to use data from Apollo lunar rocks, which recorded the impact of Clashes from the moon, Mars and Mercury. Previous hypothetical studies have also built three-dimensional computer models that simulate meteor attacks. Abramov and Mojzsis included a meteorite size model, frequency and distribution estimates to chart earth's damage during this period. It is thought that the intense bombing event lasts from 20 million to 200 million years.

The 3D model allows Abramov and Mojzsis to adjust the temperature below independent cracks in order to assess the heat and cold of the earth's crust after major collisions, thereby assessing the survival of the organism. . Research shows that less than 25% of the earth's crust is melted during an attack event.

The strike on Earth by meteorites from 3.9 billion years ago may have boosted life on earth, according to a new study by the University of Colorado. (Photo: NASA / JPL)

The researchers at the University of Colorado - Boulder even increased the intensity of meteorites in the model by up to 10 times - if this true fact exists, it could completely vaporize the oceans on the left. land. Abramov said: 'Even under the harshest conditions we have proposed, the earth cannot be completely destroyed by meteorites'.

Instead, hydrothermal water circuits may have provided refuge for temperature-loving organisms and harsh environments, called hyperthermophilic hyperthermophilic bacteria. Even if life did not form 3.9 billion years ago, such shelters would become an appropriate cradle for life on earth, Mojzsis said.

The researchers concluded that underground microorganisms living in the thermal range between 175 degrees and 230 degrees Fahrenheit could proliferate during the period of this violent bombing. Research models show that underground habitats for such microorganisms increase with volume and time under the influence of intense influence. Some of the Earth's microorganisms today, including the so-called 'hard-boiled microorganisms' that live in hydrothermal vents in Yellowstone National Park, can still thrive. strong at 250 degrees F.

Geological evidence shows that life on Earth was present at least 3.83 billion years ago, according to Mojzsis. 'Therefore it is not unreasonable to say that life has existed on Earth for more than 3.9 billion this year. We know from the geochemical information that our planet is clearly a place to live at that time. This new study addresses a major problem of the origin of life by eliminating the need to have many sources of life on earth. '

Most planetary scientists believe that a large planet like Mars attacked the earth 4.5 billion years ago, causing itself and the earth to partially evaporate. The collision may have caused a giant cloud from which the moons, then our entire moon, congregated into a mass. 'That event happened before the meteorite attack was at least 500 million years ago, it effectively hit the earth's re-establishment button.'

Mojzsis said : 'But our results suggest that no event since the formation of the moon has the ability to destroy the earth's crust, and sweep away any existing biosphere. Instead of cutting down the tree of life, we think that the meteor bombing actually cut it. '

The results also support microbial life possibilities on other planets such as Mars and even planets filled with earth-like planets in other solar systems. According to Abramov, they may have been plowed back to the surface by certain effects.

Scientist Michael H. New - NASA's cosmological principles department and directed the Evolutionary Biology and Extraterrestrial program - said: 'The exact time that life originates on the left Land is a controversial issue. These findings are significant because they show that life may have begun before meteorites attacked the earth during the Hadean era from 3.8 to 4.5 billion years ago . ' Research conducted by Abramov and Mojzsis is funded by NASA's Department of Evolutionary Biology and Evolutionary Biology. The Evolutionary Biology and Alien Biology Program supports studies of the origin, evolution and distribution of life on Earth as well as the possibility of survival in other planets. Mojzsis is a member of the NASA Moon Research Institute of the Moon's Origin and Development Center.

References:
Oleg Abramov, Stephen J. Mojzsis.Habitability microbial of the Hadean Earth during the late heavy bombardment.Nature, 2009;459 (7245): 419 DOI: 10.1038 / nature08015