Did nasa really announce that Nibiru or planet x is heading for the earth?

Okay no bs when answering it my mother is one of those dooms day chicken littles and just told me that nasa announced on the official nasa website that the planet x or 'nibiru' is going to pass by the earth and mess with our sun. I've been hearing this since 2009 when it was originally supposed to happen and it didn't and back then people claimed that nasa announced the same thing and it didn't. A few weeks ago a guy that is one of the founders of the sites she gets her info from told her that he didn't think it was going to happen and it quieted her for a little while but she started talking about it again. I'm really really sick of hearing all of this. Can someone please give me valid information about this so I can shut her up and calm her down.