Carbon Dating and the Dangers that Outside Forces May Pose
Due to processes contributed by the scientific community, such as carbon dating, the rest of society can contribute to humanity’s understanding of our world and its most complex inner workings, including tracing back an object’s date to millions of years.
Carbon dating is a radioactive dating process which can only be used on once living objects who were once at equilibrium with the atmosphere in taking in carbon dioxide. Primarily, this can refer to plants which undergo photosynthesis, in taking in carbon dioxide and releasing oxygen. However, this can also refer to animals who ingest the plants, as they are also ingesting the element used in carbon dating: carbon-14. On Earth, there are cosmic ray protons which originate from somewhere in space. These protons shoot their nuclei in the atmosphere, which in turn produces neutrons to bombard the nitrogen in the atmosphere. From this transmutation reaction, carbon-14 is created, where it can combine with oxygen to form carbon dioxide. Therefore, this carbon-14 is continually being absorbed by the plants on Earth and then ingested by all animals, whether they consume the plants directly or whether they eat other animals who are herbivores. Since the carbon-14 is constantly being created by the bombardment of nitrogen, scientists can measure the amount of substance in the atmosphere versus the amount that has been emitted from a once-living object. Once a living thing dies, they begin to emit carbon-14. According to hyperphysics.phy-astr.gsu.edu, “Carbon-14 decays with a halflife of about 5730 years by the emission of an electron of energy 0.016 MeV. This changes the atomic number of the nucleus to 7, producing a nucleus of nitrogen-14. At equilibrium with the atmosphere, a gram of carbon shows an activity of about 15 decays per minute”
(See Figure 1). From an understanding of carbon dating, scientists have used the process to date back objects such as trees, animals, and even humans. However, this process may be in danger.
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| Figure 1 |
From a study conducted in 2015, research was found showing that emissions from fossil fuel may limit carbon dating. When pumping the fossil fuels, another type of carbon is released into the atmosphere. This new carbon combining with the carbon-14 may confuse the real ratios of the carbon-14 in the atmosphere, which creates a diluted effect. Dr. Graven explains, "If we did any current measurements on new products, they will end up having the same fraction of radiocarbon to total carbon as something that's lost it over time due to decay," said Dr Graven. For example, in 2050, if this process continues to occur, a shirt would appear to be the same age as a piece of clothing wore by William the Conqueror. The exact severity of this problem will depend on how much the emissions will increase over the next couple of years. For instance, if the emissions continue to grow at the rate they are, they could reach an age of 1000 years by 2050 or 2000 years by 2100.
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I find this topic very interesting because I did not know that if people continue removing of fossil fuel from the ground will affect the experiment of using radiocarbon to identify the age of an object. Where specifically is cosmic ray protons from? How are these ray produce?
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