Of course NASA would publicly announce it. Why wouldn't they? They're human beings that live on the same planet as we do. Conspiracy theories are invented by people in an attempt to explain why they have no proof for their made up stories, like Nibiru. That is not science. For science, you need evidence. You need data. I assure you, even if NASA was some evil organization (that works for the Illuminati, right?) that wanted to hide impending cataclysm from the general public (why? If the world is going to end, why does it matter if there's mass hysteria?), they are far from the only organization in the world that would be able to detect the presence, even indirectly, of an object such as Nibiru. There are private citizens that could do that. That means your conspiracy theory would require that tens of thousands of people, if not more, to not only keep the biggest secret in the history of human civilization, but also hide any and all evidence of it. That is, for all intents and purposes, impossible. Especially in this day and age. There is not one single reputable scientist in the world that will assert the existence of Nibiru. That should be all it takes to convince you. If it's not, you need to learn critical thinking and healthy skepticism. You need to learn science literacy. Real science, not the ridiculous made up crap you're getting off the internet. Anyone can have a website, you know. That includes crazy people, stupid people and unethical people whose mission in life is to take advantage of the naive for various reasons. Don't be naive. You're smarter than that.