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xkcd #3281: Antiques Roadshow
(thelemmy.club)
Title text:
The family lore was that we've had it ever since it was ejected from a star-forming gas cloud, but it seems more likely that my great-grandparents probably just bought it while on vacation in the galactic thin disk.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3281/
They were numbered in the order that they were "discovered" (or theorized, in the case of population III). Similar to how exoplanets around a particular star are designated "a", "b", "c", etc. in order of discovery, so they usually end up not in any particular order in terms of orbital radii or size. Sometimes letters end up skipped when a letter is assigned and then it's discovered to be a false positive.
So there's logic to it, just not the logic one might prefer.