How old is the earth?

Have you ever wondered how one day one of you is the age of the earth? I think a controversial question was already over the past three centuries past, in 1654 one of the researchers who called John Lightfoot offered to answer this question and said that the earth was created in exactly nine o'clock on the morning of 26 October 4004 BC, based on his calculations on the Bible.

In the seventeenth century the world called the Comte de Buffon heating the sample similar in composition to the ground with making and based on the rate of low temperature by estimating the age of the Earth is about 75,000 a year.

In the nineteenth century, a scientist Lord Kelvin equations and using some of the age of the earth as much as 20 to 40 million years old, and this was the last attempts until it was discovered the radioactivity of the material and its use in determining the age of different materials by measuring the rate of decay. This is the method currently used to determine the age of rocks and fossils and archaeological samples and even samples that come by astronauts from the moon and Mars, and based on that method has been estimating the age of the Earth is about 4.54 billion years margin of error of less than 1%.

Now you can respond to this question .. How old is the universe?

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