How did we determine that the sun is ~4.6 billions years old?

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I love astronomy stuff, not an expert at all, but have always been so fascinated by it. I am totally baffled by how we seem to claim that we can approximate how long the sun has been around. Like the margin of error for a number like that is crazy…. totally incomprehensible to me. Say that we are 25% off, that means we are over 1 billion years off. So, how do people confidently claim that the sun is 4.6 billion years, rather than 3 billion or 10 billion?

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Anonymous 0 Comments

The sun is what’s is called a “main sequence star.” Stars like the sun follow a predictable lifecycle of forming, burning, changing characteristics over their lives, and then dying one of several different ways.

We know this fairly accurately through a combination of observations and calculations.

We can easily plot the sun on a table of measured size, mass, luminosity, composition, and other factors to get us a good idea of its age.

Also, the fact that all the planets formed at the same time as the sun and we can also measure *that* helps us get a good picture of when it was formed.

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