How many years was the earth born, and how many billion years ago was life on the earth born?

4.6 billion years ago.

Today's scientists tell us that the Earth is 4.6 billion years old. However, how did this conclusion come to this? Human beings living on the earth have been very concerned about the age of the earth since ancient times, but due to the lack of scientific methods to calculate the age of the earth in ancient times, the age of the earth has always been a mystery.

In this context, the claim that some church priests in Western countries claimed that the earth was created by God in 4000 BC has led many to believe this nonsense.

How can we scientifically estimate the age of the earth?

In the 17th and 18th centuries, scientists tried to estimate the age of the earth by studying the salinity of the oceans. They assumed that the sea was originally salty and that it was the salt that washed the water into the ocean. Knowing the current salinity of the seawater and how much salt the world's rivers can flush into the ocean each year, we can calculate the age of the ocean, and further calculate the age of the earth.

Because whether the sea was originally thin or not is itself a mystery, the amount of salt that rivers bring into the ocean varies from year to year, and it is not known how many years before the formation of the ocean. Therefore, this approach does not solve the problem.

There are also scientists who want to estimate the age of the Earth by measuring the annual sedimentation rate of the oceans. They believe that the age of the ocean can be calculated by calculating the annual sedimentation rate of the ocean, and then measuring the total thickness of the ocean's sediments. However, since the seafloor is constantly in motion, and the sediments on the seafloor are constantly changing, this approach is also untenable.

In the 19th century, after Darwin proposed the theory of evolution, people found a way to determine the relative age of rocks through the study of fossils, but the absolute age of the earth itself could not be estimated by this method.

In the 20th century, scientists finally found the most reliable method for determining the age of the Earth, called isotope geometry.

In the early 20th century, it was discovered that trace amounts of radioactive elements were found in the earth's crust, and their nuclei could automatically release certain particles and turn into other elements, a phenomenon known as radioactive decay. Under natural conditions, the rate of decay of radioactive elements remains stable regardless of external physical and chemical conditions.

For example, 17.4 billion grams of uranium decay into lead and helium after one year. With the decreasing mass of uranium, after about 4.5 billion years, roughly 1.2 grams decay into lead and helium. Taking advantage of this characteristic of radioactive elements, we can accurately calculate the age of the rocks by selecting uranium-bearing rocks and measuring the uranium and lead content in them.

The oldest rock on Earth is estimated to be about 3.8 billion years old using this method. Of course, this is not the age of the Earth, because before the formation of the Earth's crust, the Earth went through a period of molten surface, and scientists believe that with this period, the age of the Earth should be 4.6 billion years.

The isotopic age is 4580 mA, which is about 4.6 billion years ago.

Quote Part: In fact, the question is inconclusive. The so-called 5 billion years is extrapolated from the oldest stone old. But I personally don't think that the age of the Earth can be extrapolated from this. So the age of the Earth should be greater than 5 billion years".

Pudishu teaches 4600ma, but Tian Jun said that many things are inconclusive, so it's better for you to search on google, many ** have professional research, and there are more conclusions after 8".

Determination of isotopic age (absolute age).

Methods for determining age (absolute dating) have been explored for a long time, and it was not until the discovery of radioactive elements that a convincing and scientifically supported method of dating was found, which is isotope dating.

Principle: According to the analysis of the content of the parent isotope and the content of the daughter isotope of the radioactive elements preserved in the rock, how long can there be such a ratio of the child body to the parent body, the key is the fixed decay constant of the radioactive element.

t=1 ln(1+d n) decay constant.

It calculates the age at which the isotope was formed, which is the age at which the rock is formed.

In order to guarantee the accuracy (accuracy) of dating, the elements used for dating should be present.

long half-life; It is easy to separate in rocks and has a large content;

It is easy to preserve and is not easy to lose in the geohistory.

Commonly used dating isotopes k ar rb sr u pb

C140 is commonly used in new (Cenozoic or archaeological).

Note: The isotope dating method and principle are scientific, but there are dating errors because the content of d and n is not easy to test or is incomplete (lost) in the geological history. Geohistory is recorded in millions of years.

Note: MA million years.

Magmatic rocks are formed by geological movements within the Earth.

Therefore, its formation age is later than the formation of the earth.

There are about 100 million years old"Breeding"The stage, which is a mixture of solid and gaseous matter, but is also a sphere, also revolves around the sun, so there will be 4.6 billion years and 4.5 billion years.

4.6 billion years is the lower limit, and the upper limit is a quadrillion year.

That is, the age of the earth must be in between.

4.6 billion years? It seems that human beings are so small

About 4 billion years old.

The history of life refers to the history of the development of life, which has existed on the earth for 3.8 billion years, and has been constantly changing since its birth, continuing and evolving in the midst of change.

This is a real, long, and unfinished historical process. The history of life is not only the history of biological evolution, but also the history of the evolution of the earth, the history of the entire natural world (living and non-living parts). Life on Earth is as old as the oldest rocks on Earth, that is, in the early Archean (3,53.8 billion years ago), life in cellular form appeared.

Throughout the entire history of life on earth, from the origin of life to human civilization, it can be roughly divided into three stages.

1. The chemical evolution stage of pre-life.

Fossil evidence and stable isotope analysis of the Archean in Australia and South Africa show that life on Earth is as old as the oldest rocks on Earth, i.e., in the early Archean period (3.538 billion years ago), when life in cellular form appeared. If the chemical evolution of prelife took place on the Earth's surface, then this could only have happened 3.8 billion years ago and 4 billion years ago.

Why: Geologists – The Earth's crust has been gradually forming since about 4 billion years ago.

2. Biological evolutionary stage.

The birth of the earliest cellular life on Earth, that is, the first appearance of morphologically characterized and individual life with biological membranes separated from the outside world and internal membranes, marked the completion of the chemical evolution of pre-life and the beginning of biological evolution. The biological evolution that began with the emergence of the earliest cellular life has gone through three geological epochs: Archean (3.8 billion years ago, 2.5 billion years ago, 2.5 billion years ago), Proterozoic (2.5 billion years ago, 600 million years ago), and Phanerozoic (600 million years ago to the present), which lasted for 3.8 billion years.

3. The parallel and mutually restrictive stages of cultural evolution and biological evolution.

In the last few thousand years of the last few thousand years of the Phanerozoic, human beings on the earth entered the stage of civilization, and since then, the evolution of the biosphere has been more and more influenced and controlled by human activities, and human culture and biological evolution have interacted and restricted each other, which is the characteristic of the last stage of life history.

Summary. The formation of the earth took about 100 million years to come. Scientists have reconfirmed the age of the Earth, believing that the Earth was created much later than the solar system, spanning about 100 million years.

How many years has it been since the Earth was born?

I have received your question and am in the process of answering it.

The formation of the earth took about 100 million years to come. Scientists have reconfirmed the age of the Earth, believing that the Earth was created much later than the solar system, spanning about 100 million years.

If you have any other questions, please feel free to ask me.

In the 21st century, scientists have reconfirmed the age of the earth, believing that the earth was created much later than the time of the solar system, spanning about 100 million years, which is much later than the previously thought 30-45 million years. Previously, scientists calculated that the solar system was formed 100 million years ago through the formula for calculating the age of the solar system, and the age of the earth was about 3 billion to 4.5 billion years later than the solar system, about 100 million years ago. In 2007, Swiss scientists revised the data to conclude that the Earth was created 62 million years after the formation of the solar system.

Scientists generally calculate the age of the Earth and the Moon from two radioactive elements, hafnium-182 and tungsten-182. The decay period of hafnium-182 is 9 million years, and the isotope after decay is tungsten-182, which is one of the components of the earth's core. Scientists believe that almost all of the hafnium-182 element had decayed into tungsten-182 by the time the Earth was formed.

Only a very small amount exists, and it is this trace amount of hafnium-182 that can help scientists calculate the true age of the Earth. "It takes 5 billion to 6 billion years for all hafnium to fully decay into tungsten, and it sinks into the Earth's core, and the new one shows that the Earth's and Moon's mantles contain more elements than the Solar System, and have been estimated to be about 100 million years old," said the professor at the Niels Institute

Suitable for many rocks composed. Also with Venus, Jupiter, Mercury, Mars, Saturn in, those many rough stones. Someone gave the new ball a name Earth.