The Sun is estimated to be about 10 - 20 million years older then the Earth, and by radioactive dating, the Earth is about 4.75 billion years old, so that the Sun is therefore around 4.76 billion years. There are uncertainties inherent in radioactive dating so ages from 4.6 to 4.8 billion years are probably reasonable. Note, some of the oldest meteorites are 4.8 - 4.9 billion years, but the trapped dust grains can be much older than the Sun because dust grains are often formed in old stars 10's to 100's of millions of years before they got to the cloud out of which the Sun and planets formed.
Copyright (C) 1997 Dr. Sten Odenwald
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