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The last form of life on Earth will fall through to 2.8 billion years old, burnt down a dying Sun is a red giant. In about a billion years before that, the only living things on the planet will remain single-celled organisms, hiding in isolated hot and salty waters.
This bleak forecast for life on Earth, but a ray of light for those who are looking for life on other planets. After all, thereby reviving the hope of finding it in places that previously were considered inhospitable.
Jack O'malley-James of Saint Andrews University (UK) and his colleagues on the basis of what we know about the Earth and the Sun, has calculated the chronology of withering life and tried to extrapolate data to other planetary systems. Taking into account, of course, that sun-like stars age differently depending on their size. "Habitability is not immutable characteristic of the planet, much like it has its own history", - the expert marks.
Scientists began with modeling of growth temperature on the Earth's surface at different latitudes, not forgetting about the changes in the planet's orbit. The first thing from her face will disappear plants, mammals, fish and so on, then invertebrates. The oceans will evaporate, tectonics will stop, because there will be lubrication for the movement of the plate - water. Only at high altitudes, in caves and deep beneath the earth will still remain small reservoirs of hot brine. Microorganisms adapted to such conditions, will rule the Earth about a billion years. Then will not become them.
Extrapolation to the planetary system of stars of various sizes showed that bodies like the Earth, in the first 3 billion years is nothing but a single-celled. Complex forms of life might exist for only a relatively short period of time before dying light, then everything is back to microorganisms. Thus, the chances of finding a complex life on other planets is very small.
But of astrobiologists it is not sad. Any hint of the existence of the most primitive forms will be a great breakthrough and happiness. Perhaps those planets which seem uninhabited, are just at the stage where they are born or die (but still there) life, and this is important.
The study is published on the website arXiv.org.
Prepared according to NewScientist.