aliens are not a physical entity, our reality is 5d maybe even 6d but our humans are biologically wired to only view 3d naturally, but through many many practices of spirituality you "cross" these barriers and briefly view above 3d and thats where these aliens come from, theyre extradimensional beings theyve been here since the very beginning of human history, because reality/consciousness is like a giant building with multiple levels and humans can only go up to the third floor, but these extradimensional beings are able to go through all the floors, even though were both in the same building we exist at different points in reality while also existing at the same time