How Scientists Calculate the Age of Ancient Fossils (Billions of Years Old)

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By Bangladesh Reports

Have you ever held a fossil in your hand and marveled at the thought of a creature roaming the Earth millions, or even billions, of years ago? But how scientists calculate the age of ancient Fossils remains? It’s not just about educated guesses or counting growth rings like a tree! The Process is known as Carbon Dating.

How Scientists Calculate the Age of Ancient Fossils

The Secrets of Carbon Dating Method

Carbon dating is used to determine the age of fossils, corpses, and even civilizations. Ordinary carbon is not radioactive. It has an isotope. Normal carbon is called carbon 12. Its other isotope is carbon 14. 14, because it has two extra neutrons in its nucleus, both of which undergo fission.

The atomic mass of carbon 14 is 14. Again the atomic mass of nitrogen is 14. The difference is actually in the number of protons and neutrons. Nitrogen nucleus has 7 protons and 7 neutrons. On the other hand, carbon 14 has 8 neutrons and 6 protons.

But Here’s the Funny Thing:

Radioactive carbon, i.e. carbon 14, is constantly being created on Earth. How?

With the help of nuclear reactions. Neutrons from space are helping that reaction. Cosmic rays or radioactive rays are constantly reaching the Earth from space. These rays contain various particles and waves. A major element among them is the neutron. Its biggest provider is the sun itself.

From Nitrogen to Carbon: The Birth of Carbon-14 

Neutrons from cosmic rays are hitting the atmosphere. As a result, who knows what happens to other components of the atmosphere, nitrogen gas is affected. High-speed neutrons are hitting the nitrogen nucleus. As a result, the nitrogen nucleus breaks down. As a result of the collision, a proton is knocked out of the nucleus and a neutron from space is added. So in the nitrogen nucleus, the number of neutrons is 8 and the number of protons is reduced to 6. The number of protons in the nucleus is actually the atomic number of an element.

The religion and properties of the atom depend on the atomic number. Regardless of the number of neutrons, having 6 protons in a nucleus means that it is a carbon atom. Due to the impact of neutrons, the change of the nitrogen nucleus results in a decrease in the number of protons. So it can no longer be called a nitrogen nucleus. It will then behave like a carbon nucleus. So the nitrogen nucleus will change form and become a carbon nucleus.

The nitrogen nucleus will become the carbon nucleus, but what about the 7 electrons that were outside the nucleus? Since the 6 electrons will be bound by the attraction of the 6 protons, the remaining electron may then escape from the attraction of the nucleus. This is how carbon 14 is born. But one problem remains. A nucleus the size of carbon 6 can comfortably hold 6 protons and 6 neutrons. But it struggles to accommodate the extra two neutrons. The nucleus cannot remain in a stable state. So soon break up in that nucleus. A neutron is converted into a proton by irradiating beta rays. As a result, the number of protons increases, neutrons decrease by 1. The nucleus returns to its original state, with 7 protons and 7 neutrons and becomes a full-fledged nitrogen nucleus. Then a free electron is captured from the outside and becomes a nitrogen atom of the previous appearance.

Formulas for Nitrogen to Carbon and Carbon to Nitrogen Here nitrogen released from cosmic rays hits the nitrogen nucleus. The result is a nucleus of carbon 14 and a proton. Again the nucleus of radioactive carbon emits radioactive rays giving birth to a stable nitrogen 14 atom. An electron and an antineutrino are born with the formula for nitrogen to carbon and carbon to nitrogen. Here nitrogen released from cosmic rays hits the nitrogen nucleus. The result is a nucleus of carbon 14 and a proton. Again the nucleus of radioactive carbon emits radioactive rays giving birth to a stable nitrogen 14 atom. An electron and an antineutrino are also born

But this whole process takes some time to happen. By then some, if not all, of the radioactive carbon has formed chemical bonds with oxygen. As a result, radioactive carbon dioxide is produced. Again, radioactive carbon can produce nitrogen by irradiating radioactive carbon dioxide. But before that, the plants absorb some of the radioactive carbon from them. They use sunlight to make their food. Then these carbons again become part of the plant body. That plant is then eaten by herbivores and omnivores like humans. Herbivores are then eaten by carnivores at the top of the food web. In this way, radioactive carbon spreads from plants to all animals on earth. Don’t think that plants only make their food with radioactive carbon dioxide. Instead, the plants absorb both types of carbon, ordinary and radioactive. They cannot distinguish. Carbon is constantly entering the body of living plants and animals as food. Radioactive carbon is also present in living organisms. However because there is a constant supply of radioactive carbon, the number does not fall below a certain ratio.

The whole thing happens in such a way that the ratio of stable and radioactive carbon in the body of any living organism is always equal, i.e. 1:1. But after the death of the animal or plant, all carbon supply is stopped. Carbon 12 does not break. Therefore, the amount of carbon in plants or animals does not change. Yes, organisms decompose. Bark, skin, flesh, etc. decompose and mix with soil. But what remains intact as a skeleton or wood is sufficient to determine the age. The ratio of carbon 12 to carbon 14 in whatever part is found in the intact corpse

Limitations of the Time Machine: Exploring the Range and Requirements of Carbon Dating 

Tt’s important to remember that carbon dating has its limitations. It method only works on organic materials, meaning things like metal swords or stone structures age can’t be calculated in this method. Additionally, its dating range is like a detective’s caseload, limited to around 50,000 years. While perfect for studying recent human history and the latter stages of the Ice Age, it can’t quite reach the depths of dinosaur eras.

If we combine this with other dating method and historical research, we will get better results. It’s like solving a giant puzzle but one piece at a time. Together, they help us see the bigger picture of our planet’s and humanity’s long and fascinating journey, allowing us to connect with the whispers of the past through the objects they left behind. This is your story, unfolding in real time. Be a part of it.

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