The reason for not announcing it is due to religious beliefs it would cause the world to go into panic. It was discovered by NASA probes Pioneer 10 and 11 in 1983 and was announce on the Paul Harvey news cast as a possible 10th planet but when our government realized the implications of an incoming body which has its unique elliptical orbit around two suns.
(Our Sun has a dead twin). It has turned into a national security issue, our government knows and is afraid of panic. The whole story of planet X (Nibiru) one of many names for Planet X comes from ancient clay tablets 4000 BC describing a tenth planet and its life on it. They were called The Anunnaki which means in Sumarian language they who came from heaven to Earth. The Summering land is where IRAQ is now. Ancient Sumer was the first civilization on the planet (to date). It was ushered in by the Anunnaki, who taught the people music, the sciences, astronomy, languages (both spoken and written), mathematics, herbology, manipulation of the environment, hybridization of crops, genetic manipulation of livestock, religion, sexual promiscuity, war, mining for resources, jewelry-making, tailoring, blacksmithing, architecture, art, poetry, human sacrifice, and the whole gamut of "civilized behaviors." In fact, these events are not only outlined in the writings of the ancient sumerians, but also in the Bible, the pseudopigraphia of the Hebrews [1] and the ancient texts of the Hindu. The word NIBIRU means planet of crossing. It has a history or else I would take this as all BS. These Anunnaki were giants they were 8 to 10 feet tall. They used the inhabitants to dig for gold they needed for there atmosphere. I believe in UFOs and the possibility that these aliens was the cause of all religions. This is what our government is afraid of us finding out the real truth.
I have been studying Planet Xes history on xfacts.com and zetatalk.com for five years now. Planet X orbits two suns about every 3657 years and is in our solar system now it is four times the size of Earth and it's mass = 23 Earths. Planet X has many names from most countries, the most common name is Nemesis. This is what's causing the Earth changes and disasters were seeing today. Our planet weighs nothing in space any magnetic disturbance will have disastrous affects on weather and tectonic plates and volcanoes. Planet X caused the Great Flood there was a pole shift that melted the poles. They said that this coming pole shift will be worst the Earth's outer crust not the oceans will rotate 90 degrees because the Earth will line up with Nemesis as it crosses our skies. The Bible calls Planet X (Wormwood). The Incas called Planet X (Hercolubus), The Babylonians called Planet X (Marduk), the ancient Hindu astronomers named Planet X Treta Yoga and the destruction it causes Kali Yoga. So it has a history which makes it real. Almost every time it comes into our solar system it affects the surface of every planet it crosses. It's coming in from our blind side (sun side). There seems to be a Government cover-up on this subject matter. WHY? Do they fear panic? We must warn people for survival reasons if theirs a fighting chance to survive we must take it.
To summarize what I'm saying here I was inspired by the 50 years of work done by Zecharia Sitchin who translated the ancient Sumarian text that was made 6000 years ago.