Astronomers use metal to mean elements other than hydrogen and helium. Metals in the chemists sense of the word aren't in general necessary. A lot of life is pure CHONPS. However, most complex life involves some amount of metals in the chemical sense (most animals require both iron and selenium for example). And planets which are of low metalicity in the astronomical sense will be necessarily be of extremely low metal content in the chemical sense, since in order to get the actual metals other than just lithium and beryllium require extensive synthesis cha... (Read more)(Click to expand thread. ⌘F to Expand All)Cmd/Ctrl F to expand all comments on this post

Astronomers use metal to mean elements other than hydrogen and helium.

Wow, Astronomers are lazy. It's not hard to make up new terms for things when the existing ones clearly don't fit. Heck, if making up a word was too difficult they could have used an arbitrary acronym.

1John_Maxwell7y Thanks for the clarification!

Open Thread, September 1-15, 2012

by OpenThreadGuy 7y1st Sep 20121 min read360 comments

6


If it's worth saying, but not worth its own post, even in Discussion, it goes here.