Some believe we exist in a binary star system and that our sun has a "brown dwarf" partner in eliptical orbit with it....

Some have called this planet Nibiru/Wormwood/The Destroyer...

The last name is because it is postulated to be on a 3600 year orbit relative to our planet, and every time it swings close by, big changes happen on the planet.

Not trying to profess what "science" hasn't proven yet, just throwing it out there.