[Strategerist]

How do they know it’s from Mars? Does it have “If found, please return to Marvin” inscribed on the bottom?

Of course, you couldn't be bothered to click the link and read any of the actual article.

They know it's from a planet because it's too young - asteroids are all over 4 billion years old, but this rock is about 2 billion years old.

And the composition closely matches that of rocks sampled by the Mars rovers on Mars.

This was all determined after 6 months of painstaking work.

[The Cajun]

asteroids are all over 4 billion years old

Dang, must have missed reports about the mission that surveyed all asteroids and determined their age.
Must have been a really ambitious endeavor.
Another wonder of science :)

[itsahoot]

This was all determined after 6 months of painstaking work.

I am sure no government funds were involved. Two Billion, four Billion, years no room for doubt there.

Speculation is not science and neither is shouting at skeptics.