I believe they say it's all lies as NASA always lies. Which I find wierd seeing that they also claim NASA admits the earth is flat because of a paper that includes the following "This report details the development of the linear model of a rigid aircraft of constant mass, flying over a flat, nonrotating earth". I would expect that since NASA always lies, that statement should be a lie as well and not an admittance of the true shape of the earth. But hey, who am I to understand flat earth logic.
Also, the fact that the Shoemakers and David Levy discovered the comet from an observatory owned and operwted by Caltech (not NASA) and observations were conducted by various professional bodies around the globe should make a difference but we know flat earthers call all scientist paid NASA shills even those that made their discoveries before the discovery of the continent of America talk less of the creation of the US.