Nasa, and all other scientists, professionals, and amateurs alike, which indirectly includes pretty much the entire world. The conspiracy of the heliocentric model, for the purpose of lying to us. because in the end, what would be the purpose for lying that space exists and that lunar eclipses are there because of large invisible objects.

O wait, did I just bait a trap? nah, just pointing out there isn't any discernible benefit for people to take part in such a conspiracy that has little to any impact on regular people but it affects the work of everyone else, who seemingly have been making accurate predictions based on a model that is a lie, and keeping a conspiracy in place that has no defectors that blew the whistle on this, regardless of it's enormous scope and how many participants it requires.