This is a very interesting thing. The article didn't mention anything about how so much carbon was there in the first place. From the article abstract: So it looks like the gas the system coalesced from could have been carbon-rich. I didn't realize there was so much carbon out there.The identification of a carbon-rich super-Earth means that distant rocky planets can no longer be assumed to have chemical constituents, interiors, atmospheres, or biologies similar to those of Earth, Madhusudhan says.
A carbon-rich 55 Cancri e is also plausible if its protoplanetary disk bore the same composition as its host star, which has been reported to be carbon-rich.
According to the end of the paper, it appears to be challenging the traditional assumptions that rocky exoplanets would have similar compositions to what we have here.Numerous studies have suggested the possibility of carbon-rich exoplanets ... However, the prevalent practice is to assume Earth-centric compositions, comprising of Fe, silicates, and H₂O, in explaining super Earth observations. A carbon-rich 55 Cancri e would represent a departure from Earth-centric mineralogies in rocky exoplanets.