adult singles dating kennebunk maine - How old is the earth radiometric dating
The expansion of the universe gives an age for the universe as a whole: 13.7 billion years old.
Astronomers and geologists have determined that the universe and Earth are billions of years old.
The only problem is that we only know the number of daughter atoms now present, and some of those may have been present prior to the start of our clock. The reason for this is that Rb has become distributed unequally through the Earth over time.
Prior to 1905 the best and most accepted age of the Earth was that proposed by Lord Kelvin based on the amount of time necessary for the Earth to cool to its present temperature from a completely liquid state.
Although we now recognize lots of problems with that calculation, the age of 25 my was accepted by most physicists, but considered too short by most geologists. Recognition that radioactive decay of atoms occurs in the Earth was important in two respects: Principles of Radiometric Dating Radioactive decay is described in terms of the probability that a constituent particle of the nucleus of an atom will escape through the potential (Energy) barrier which bonds them to the nucleus.
Using the known rate of change in radio-active elements (radiometric dating), some Earth rocks have been shown to be billions of years old, while the oldest solar system rocks are dated at 4.6 billion years.
Astronomers use the distance to galaxies and the speed of light to calculate that the light has been traveling for billions of years.
Earlier research had shown that isotopes of some radioactive elements decay into other elements at rates that can be easily predicted.