On Sept. 29, 2011. NASA hold a conference for updating information about the database of near-Earth asteroids in our solar system, tracked by Wide-field Infrared Survey Explorer (WISE) telescope.
Someone in a phone call from media asked about Planet X aka NIBIRU (4:13 Sec. onwards)and the answers provided by NASA, took the acronym "Never A Straight Answer" to a whole new level..
When media reported caller asked Amy Mainzer from JPL who is head of the NEOWISE project about planet X.
She had responded by saying there isn't anything hazardous out there but " if there is, it would be a large body in a roughly circular orbit" - she was then pushed by the caller again and she comments the object of concern may be a brown dwarf star but these stars are not in the vicinity of our solar system.(YET)
Amy is an American astronomer at JPL specializing in astrophysical instrumentation and infrared astronomy. She is the Deputy Project Scientist for the Wide-field Infrared Survey Explorer and the Principal Investigator for the NEOWISE project to study minor planets