The Greeks consider the first Olympic Games as the beginning or 776 BC.The Muslims count the Prophet’s departure from Mecca, or the Hegira, as their beginning at AD 662.The Mayan calendar used 3114 BC as their reference.More recently is the radiocarbon date of 1950 AD or before present, BP.Radiocarbon dating, which is also known as carbon-14 dating, is one widely used radiometric dating scheme to determine dates of ancient artifacts.In discussions of the age of the earth and the antiquity of the human race, creationists often assail perceived weaknesses in radiocarbon dating. Morris, for instance, wrote, "Despite its high popularity, [radiocarbon dating] involves a number of doubtful assumptions, some of which are sufficiently serious to make its results for all ages exceeding about 2000 or 3000 years, in serious need of revision." [Morris2000, pg. Radiocarbon dating is based on the fact that the interaction of cosmic rays from outer space with nitrogen atoms in the atmosphere produces an unstable isotope of carbon, namely radiocarbon.There are three carbon isotopes that occur as part of the Earth's natural processes; these are carbon-12, carbon-13 and carbon-14.
Carbon 14 has a half-life of 5,780 years, and is continuously created in Earth's atmosphere through the interaction of nitrogen and gamma rays from outer space.
Libby thus reasoned that by measuring carbon 14 levels in the remains of an organism that died long ago, one could estimate the time of its death.
This procedure of radiocarbon dating has been widely adopted and is considered accurate enough for practical use to study remains up to 50,000 years old.
Radiocarbon dating may only be used on organic materials.
Typically (6): The above list is not exhaustive; most organic material is suitable so long as it is of sufficient age and has not mineralised - dinosaur bones are out as they no longer have any carbon left.