[defrost]

The BBC (all caps) style guide splits the treatment of acronyms; BBC is all caps as it is spoken as a series of letters Bee Bee Cee.

Nasa is spoken as a single word.

From the BBC:

  Use the abbreviated form of a title without explanation only if there is no chance of any misunderstanding (eg UN, Nato, IRA, BBC). Otherwise, spell it out in full at first reference, or introduce a label (eg the public sector union Unite).

  Where you would normally pronounce the abbreviation as a string of letters - an initialism - use all capitals with no full stops or spaces (eg FA, UNHCR). However, our style is to use lower case with an initial cap for acronyms where you would normally pronounce the set of letters as a word (eg Maga, Sars, Aids, Nasa, Opec, Apec). 

* acronyms : https://www.bbc.co.uk/newsstyleguide/all

The ABC Australia style guide is a hot mess (first examples: Quantas TAFE modem are inconsistent "spoken words" and other issues) ... I'm wondering if it was last edited by an LLM or young intern.

* https://www.stylemanual.gov.au/grammar-punctuation-and-conve...