http://www.esa.int/spaceinimages/Ima...Serqet_and_Nut
In this image (on the far left side, roughly 1/3 down from the top), there is a claim of a skeleton of an alien, ribs, spine and skull, covering roughly 80 meters in size. While I would think that this is not the body of an alien, it might well be the remains of some kind of technological device of some kind. There is no way that this is some kind of natural artifact.
We need more images of this object and hopefully a full photogrametric analysis can be done to better describe this device. This image is from the original NASA/ESA sources and the issue of CGI would only arise if NASA/ESA is trying to present some kind of disclosure event and has invented this apparent device: I think not.