How long will life on Earth exist?

Fossil evidence suggests that Earth formed about 3.5 billion years ago, but the question is how long it will last and what factors can erase all life.

Life on Earth

Volcanic lava can cover a very wide surface.(Photo: Jabruson / NPL)

Volcano

About 250 million years ago, during the end of the Permian period, life was thought to be almost completely destroyed.85% of organisms live on land and 95% of organisms live in the ocean extinct . Although no one is sure what happened, there is a coincidence between the destructive large-scale activity of volcanoes and the extinction.

Compared to them, the destructive power of super volcanoes like Yellowstone does not match. In Siberia at that time, the estimated lava covered the area 8 times the size of America today. According to expert Henrik Svensen, Oslo University of Norway, it is certain that this phenomenon will repeat as it happened 200 million years ago, 180 million years ago and 65 million years ago, but cannot attend Guess the time and place.

Svensen said that the ability to destroy the life of these volcanic activities depends on the geology of the place. Volcanic eruption 250 million years ago may not be the direct cause of mass extinction, but the real culprit is salt. Siberia is a land with many salt mines. When the salt mine is heated by volcanic activity, a large amount of chemicals destroy the ozone layer, which releases into the atmosphere. Organisms do not tolerate harmful radiation from the Sun and die slowly.

Today, many salt mines still exist on Earth, like offshore Brazil or eastern Siberia. If similar eruptions occur in these areas, many species will die. However, just like that time, life will not disappear.Unicellular organisms such as bacteria will survive, almost harmless.

Collision with meteors

A large meteorite collision with the Earth led to the dinosaur extinction event. However, whether life is destroyed depends on where the collision is and the composition of the meteorite. According to the fossil record, a very large collision occurred 125 million years ago and created the famous Manicouagan crater. However, the collision did not cause mass extinction of the dinosaurs, due to the composition of the meteorite that was crystalline, relatively "inert " chemically. Conversely, if the composition of the meteorite is volatile, volatile sedimentary rock, it can produce gas clouds that change the climate in the atmosphere, causing global destruction.

According to experts, the luck for humans is that the repeat cycle of a similar collision is about 500 million years. Even if that happens, life on Earth is only completely destroyed when the meteorite is about the size of an "orphan" planet .

Earth freezes

Some scientists believe that the Earth's magnetic field deflects charged particles coming from the Sun, helping to protect the atmosphere . If the Earth's core cools, the magnetic field no longer exists, the atmosphere will disappear, meaning that there will be no life. This may be the problem that happened with Mars.

Researchers have proved that 3.7 billion years ago, Mars had its magnetic field and lost it, making the planet as cold and cold as it is today . However, according to expert Richard Harrison, of the University of Cambridge, England, if this does not happen in the near future. The Earth's magnetic field only disappears when its core solidifies completely. Currently only the inner core is solid, the outer core is liquid. The inner core increases by about 1 mm / year, while the molten core is about 2,300 km thick.

If the Earth's core cools, the magnetic field no longer exists, the atmosphere will disappear.(Photo: Alamy)

Gamma radiation explosion

Gamma radiation explosions (GRBs) are also one of the possible causes of extinction. This is considered the cause of the second largest extinction event in the Ordovician history, occurring about 450 million years ago. GRBs are created when a giant star explodes, or when two stars collide.

According to theoretical calculations, GRBs can destroy the entire ozone layer and there is nothing to prevent death of ultraviolet rays from the Sun. However, the Earth is in a relatively safe position. " If the Earth is closer to the center of the galaxy twice more, life will no longer exist," said BBC quoted Professor Raul Jimenez, University of Barcelona, ​​Spain. The twin star WR104, the closest to us and likely to cause a GRBs in the next 500 thousand years, is unlikely to harm the Earth.

Even when the Earth is influenced by GRBs, it cannot erase all life . The oceans will be radiation shields for organisms. People may no longer exist, but new life forms will begin.

The lost stars

About 70,000 years ago, a red dwarf named Scholz flew over the outer ring of the solar system, after crossing the Oort cloud. According to astronomers, it's not the first and not the last time. However, its harmful ability is very low.The probability of a larger "orphan" star Scholz becoming supernova after passing through the Oort region spreading Gamma radiation to destroy the Earth's life is very small .

Sun

In about a billion years, the Sun will be so hot that it will dry up all the oceans on Earth . Rising temperatures will kill all organisms and there are no exceptions.

Within 5 billion years, the Sun will expand and become a red giant . After 7.5 billion years, the surface will reach the orbit and devour the Earth. If you want to survive, people will have to find a way to leave this planet.

The Sun can hatch and swallow the Earth.(Photo: Alamy)

Life destroys itself

According to the Medea hypothesis by Professor Peter Ward, University of Washington, USA, the self-destruction process has taken place twice . The first time it happened about 2.3 billion years ago, a lot of oxygen was produced when photosynthetic plant life forms. Before that there was no free oxygen, leading to mass death of microorganisms.

About 450 million years ago, terrestrial plants first appeared. Tree roots hit the ground, speeding up the chemical reaction between minerals in rocks and CO2 in the atmosphere. This greatly reduces CO2 levels, reduces the greenhouse effect and pushes the Earth into a deadly ice age.

Predicting in the future, the Sun is getting hotter. As a result, the temperature of the Earth also increases, leading to a strong reaction between minerals in rocks and CO2. When there is not enough CO2 left for photosynthetic plants, they will become extinct first, leading to the disappearance of the entire animal system. According to Ward, this process will happen within 500 million years.