Did metals on earth, formed on earth? or around our sun? or somewhere else?

[Dinosaur]

Billy T: It is a bit like human generations.

Dinosaurs' post 34 is useful restatement of post 28 with the introduction of the term "stage," but may mislead one to think there are separated stages. The life expectancy of a star depends mainly on its mass. Thus some smaller "1st stage" were still existing when "3d stage" stars were. I.e. "stage" is a way to avoid the confusion astronomers created with their backwards use of "generations" but it must be understood that stages overlap in time and are not sequential.

I am younger than my niece. Counting my father as one, she is 3rd generation & I am 2nd.

I still wonder what Sol's stage is. I have never seen any credible source which provided an estimate. I do not think that a 2nd stage star would have the abundance of astronomer metallic elements existing in the solar system.

As per my previous post, I am guessing stage 4, but think that stage 5 might be as likely as stage 3.

 

[Fraggle Rocker]

I still wonder what Sol's stage is. I have never seen any credible source which provided an estimate. I do not think that a 2nd stage star would have the abundance of astronomer metallic elements existing in the solar system. As per my previous post, I am guessing stage 4, but think that stage 5 might be as likely as stage 3.

The Wikipedia article on the Sun says that it is currently halfway through its main sequence evolution, so five billion years from now it will enter its red giant phase. Eventually the Earth will be swallowed by tidal forces and cease to exist as a discrete object.

However, the sun has been becoming steadily warmer over the eons. The article says it's likely that the reason land life has existed on Earth for only one billion years is that before that it was simply too cold. One billion years from now, the surface temperature of the Earth will be higher than the boiling point of water, so all life will become extinct long before the sun's red giant phase.

That gives us a calendar for developing interstellar travel.

 

[raptorttail]

The question is a good example of why most terms need to be defined in science and not 'assumed'.

As I stated previously, as a geologist I can't write about metals without a definition of what a 'metal' is for the purpose of the study.

As for a comment that 'every 16-year-old science student knows'....actually they don't all 'know' the same definition.... and hopefully when they are a couple years older in some science 101 course that the prof will drive home from day 1 that all terms must be defined and then subsequent content be governed by those definitions.