good to know this. we'll get to know more over the years, with some changes in what we know today, and some new things, but perhaps not with surety anytime soon.
OTOH, i don't understand why agencies are spending so much money and time on exploring possibilities of life on other planets, ie, if the focus is on finding answers to the UFO-phenomenon. now NASA is planning for a mission to Europa to find possibility of life (as, according to them, Europa's oceans are twice as deep as Earth's oceans, and they may hold clue/vital signs of life). in the context of UFO-sightings and entity-contacts, there seems to be a high possibility & probability that what we've been encountering is not an extra-terrestrial phenomenon (howmuchever the 'messengers' & contactees may seem to cry), but rather arising from our very own home, or even ultra-terrestrial in nature. the entities have been very deceptive about revealing their origins, witnessed doing crazy things, and such tactics are understandable if one wants to keep a subject perennially confused, and keep the scientific community at bay from attempting to exert serious effort in studying the phenomena and just keep rebuffing the topic, which they are anyway famous for doing to issues that don't conform to the contemporary dimensions of their 'box'.