I'm reading about how this guy believes that the gods of the acient Sumerians comes from an extra planet in the solar system, beyond Pluto. He states that this planet has an orbital period of 3600 years and I wonder just how big of an orbit that is. (Pluto takes about 250 years to complete an orbit around the Sun.)
I think what the hell and go to Google for a search. BAM! Several calcuators for orbital period.
So, if the planet is out there and Earth sized then it's a little less than 250 astronomical units away from the Sun.
The internets is a strange, sometimes wonderful, place.