Though I have always loved Star Wars it is not entirely a spiritually sound mythos. Yoda, however, is an exception.
Force Ghosts are akin to the Tibetan Buddhist bliss body or rainbow light body phenomena. In turn this is largely related to the spiritual abilities of the Elves (and Merfolk too, to be sure). Force Ghosts are the result of 'becoming one with the Force' but in reality it requires actually LIVING life, enjoying ones little hut in the forest, and possessing a sense of humour which helps the nervous system permanently write memories, which state the beauty and joy and value of being ALIVE, uniting Body (Hroa) and Spirit (Fea) into one light-body.
Yoda is more of a Gnome or Hobbit from another planet than an "alien". His energetic signature is one that should be familiar to those with Atlantean (Numenorean) memories. <3