Latest organisms on Earth will become bacteria that live at a depth of many kilometers in the rocks.
This is the conclusion of scientists who have developed a computer model of the planet for billions of years.
Their main conclusion is that, as the warm sun and the temperature increase on Earth only microbes can withstand extreme conditions that will exist on our planet.
The report of that would be presented at a meeting of the National Society of Astronomy.
"In the Earth's atmosphere at that time will be very little oxygen, so these microbes must survive in a completely different, oxygen-free atmosphere, and in very salty water due to the rapid evaporation of the ocean," - says Jack James O'Malley, an astronomer at the University of St. Andrews in Scotland.
Mass extinction of species
Life on our planet depends entirely on the sun, scientists have long known that the evolution of stars of this type occurs entirely on a model.
The luminosity of yellow dwarfs like the Sun, increases towards the end of their life, and then they finish their allotted period of existence of a supernova explosion.
Astronomers from several British universities have developed a model that describes the processes that will occur in connection with the evolution of the sun on our planet in the distant future.
Roughly a billion years the solar radiation becomes so intense that the evaporation of the oceans will begin.
"After that devour the Earth's atmosphere with water vapor, which in itself is a greenhouse gas. This will create an avalanche greenhouse effect due to more rapid heating of the atmosphere, and the average temperature on Earth would be 100 degrees higher than the current" - says graduate student Jack O'Malley James.
At the same time will be rapid reduction of oxygen in the atmosphere, resulting in a massive loss of thousands of species of flora and fauna.
Shortly after the start of the process in the world will only bacteria-extremophiles, which are now live on the bottom of the ocean near geothermal sources, as well as deep in the rocks.
Scientists believe they are the only organisms that can survive in a hot, dry planet with a poisonous atmosphere. Rather, their colonies will exist around the last remaining sources of water.
After about 2.8 billion years, the conditions on the planet will become even more unfavorable, and all life will disappear from the face of the Earth.
Planet with microbial life
Astronomers believe that the study of the origins and destruction of organic life on this planet will help to understand the patterns of evolution of life in the universe.
In their opinion, the likelihood of microbial life on Earth-like planets, which are only in our Galaxy hundreds of millions, is extremely high.
Moreover, astronomers ever learn to determine the chemical composition of the atmospheres of such planets. The presence of these trace fossils of bacteria in the form of a gas is a sure sign of the existence of Earth-like life there.
"One of these indicators, the presence and activity of the bacteria is methane gas. Much depends on whether the methane product of volcanic activity, or whether it is formed by the activity of microorganisms. If astronomers of the future will be observed on exoplanets so-subtle differences in the composition of the atmosphere, it will change our understanding of the prevalence of life in the universe, "- says Jack James O'Malley.
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