This looks to me like a piece of bone, what do you think?
Very interesting find quil207 not least because it is hollow, but my gut instinct says something is not right with the base of the anomaly, do you have the link to the original image you could post as I am sure other members would like to look at this one too.
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"Creating a fiction when stating a fact destroys the credibility of the truth one are trying to convey"
Usually NASA concentrates its efforts on something that is interesting to them and will name it unusually. I was curious to know why they named this rock et-then so I enhanced it and could have found some fossil evidence.