I'd like to say the specialists, but there have been multiple religions that formed based on failed predictions (sometimes multiple failed predictions). :rofl:
Although I will point out that the logic of "why would the government cover it up?" is silly. If they thought it'd cause panic they would cover it up. They've already basically said that they'd respond that way in the past. There have been documents that state that that is how they'd respond (when possible) to things like alien contact and potential disasters (nothing to say these thing have happened, but that they would respond this way).
The main evidence is that without an active attempt to move it, it is astronomically improbable that it'd hide "behind the sun". It is theoretically possible, but would require multiple (actually a whole lot) of extremely unlikely (like, 'hitting the lottery 5-6 times in a row' style unlikely) orbital paths to all happen at the same time. Basically it'd have to be a artificially created path, and at that point there is no reason to bother. If you can move a brown dwarf then there is no reason to hide.
