I have been reading astronomy and astrophisics books for 50 years, and being a layman only understand parts of them. I just read in HyperSpace, a book by Micol (something) that Earth has heavy elements that came from the cosmic cloud that it was formed from. Okay, clear. Knew that. Then he says the Sun (which was formed from that same cloud) doesn't have heavy elements. Why?
The Sun *does* have heavy elements (elements heavier than oxygen). But heavy elements make up less than 0.5% of the entire mass of the Sun. This mass proportion of heavy elements in the Sun is smaller than that of the Earth. This is because the Sun is massive enough that it's able to hold onto large amounts of hydrogen and helium. So hydrogen and helium makes up a larger percentage of the Sun, and heavy elements make up a smaller percentage.
This page was last updated Jan 28, 2019.