<serious mode on>
Whatever the Finns are up to it's not building shelters against the imminent arrival of Planet X. It the usual crackpot theorists grabbing various unrelated facts, theories and downright lies to concoct an end of the world conspiracy.
There are lots of objects out in the far solar system, some recent discoveries are larger than than Pluto. There may even be a brown dwarf or two as well. They are very hard to spot. The thing is that they stay out there as they are in stable orbits around the sun. Thus there is no chance of them entering the inner solar system. However, there are a
lot of smaller rocks that cross the Earth's orbit and they do hit the planet from time to time. The odds are still very, very low that you will be killed by one -
Death by Meteorite So stop worrying.
<serious mode off>
Anyone fancy a rock cake?