A Little Piece of Mercury on Earth?
jonerik writes "While the discovery of meteorites believed to have originated on Mars is almost commonplace these days, the BBC is reporting the discovery of what is believed to be the first known chunk of the planet Mercury found on the Earth. The rock - actually discovered in 1999 and dubbed NWA 011 - has certain characteristics which lead experts to believe that it came from a body larger than an asteroid, and specifically from a planet."
I'd still be more inclined to trust a scientist that said "these meteorites are -believed- to be from such and such a place" or "evidence -points to- such and such an origin for this rock".
It's sort of like referring to someone accused of a crime as a "suspect" rather than a "criminal" - the distinction is very important for clear thinking.
As you say, the origin is "all but certain" - which is fundamentally different from "known" in a logical, scientific sense.
Incidentally, I noted your use of the phrase "so-called" which delineates you quite nicely from those I've been mocking. Keep up the good work; I'd mod your post up if I had any points!