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Note: this is the Astronomy definition of metal... There's Hydrogen, Helium and then there's metals.
by infradig 5y ago
Note: this is the Astronomy definition of metal... There's Hydrogen, Helium and then there's metals.
- gnulinux 5y agoWhy is this definition useful in astronomy? Why can't they just say something like "non period 1 element" (NPO element) in order not to cause accidental confusion with other branches of science?
- iwwr 5y agoJust that by volume/mass hydrogen and helium make like 99% of what's out there :)
- Gravityloss 5y agoGood question. It's all about context, which I don't know that well. But these kind of things pop up everywhere. https://en.wikipedia.org/wiki/Engineering_tolerance https://en.wikipedia.org/wiki/Engineering_tolerance
- redis_mlc 5y agoSome info on the word metal as used in astronomy: https://briankoberlein.com/post/hydrogen-helium-metal/ https://briankoberlein.com/post/hydrogen-helium-metal/ The short answer is that the fraction of metal is so low, they don't care enough to call it something else.