The Blind Force Of Design In The Mind Of God

     Deep in the Northwest Territories in Canada is the mecca of geologists in a stretch of the Acasta River.  Here are the oldest rocks on Earth, dated back for four billion years.  The dating of the Earth started in 1896 when the French physicist named Henri Becquerel discovered that uranium releases energy; and in 1903 when Pierre and Marie Curie found that radium releases a constant quantity of heat.  The Curie established that the source of energy is determined in the basic structure of the atom.  An atom is made up of electron, proton and neutron.  Carbon 12 is the most common carbon atom on Earth; and then the isotopes such as carbon 13 and carbon 14 help to determine geological time.  When an unstable isotope breakdowns, it releases energy and one or more radiation and may become a different element.  For example, uranium 238 breakdowns and releases a pair of neutrons and a pair of protons which forms thorium 234.  Being unstable, it decays into protactinium 234.  Within 13 chains of decaying, uranium 238 becomes the stable form of lead 206.  Physicists use the measurement called half-life to determine the age of a matter in the time range it takes for isotopes to decay.  For example, if a rock has one million radioactive isotopes and the isotope has a 50% chance of decaying in a year, after the first year there will be 500,000 isotopes left.  Half will decay in the second year to leave 250,000 isotopes, and so on.  Uranium 238 has a half-life of 4.47 billion years; other matters can have the half-life of only minutes or seconds.
      In 1904, Earnest Rutherford declared that radioactivity can determine the age of the Earth.  The uranium trapped inside a cooling rock would eventually decay into lead.  Using half-life and by using the remaining proportions of lead and uranium, scientists can measure the age of the rock.  Uranium 235 decays into another isotope of lead 207 with the half-life of 704 million years.  With the different tests using those two measurements for the age of a rock, the margin of error would even be narrowed down even more. 
     The combination of the atoms of zirconium and oxygen forms the crystal zircon which traps the uranium that decays into lead within a closed system.  Scientists fired a beam of charged particles of the crystal and measured the isotopes.  This system of cross checks give the measurement within a margin error of les than 0.3%.
     Carbon 14 with a half-life of 5,700 years is used to measure absolute dates on human history.  Charged particles that reach the earth from space strike into nitrogen atoms in the atmosphere and form carbon 14 then decay back into nitrogen atom and release subatomic particles.  Plants absorb fresh carbon dioxide with carbon 14 from the air and the animals that eat them maintain a steady level of the isotope in their tissues.  When something dies and stops absorb carbon 14, the isotopes decay into nitrogen.  To calculate the age of an organism, scientists measure the amount of carbon 14 still remains inside it.