Y is da titanic in da sky?

in doctor who i mean,
:)

Well the trailers make it obvious that this Titanic is a Spaceship rather than the historical ship, where the crew (The Host) and some of the passengers (Bannakaffalatta) are obviously alien. The Titanic may also have trans -dimensional or time travel capability. How else could it crash through the side of the Tardis?

Like Peter, I also think that the Eternals may have something to do with it (unconfirmed, but we'll find out next week).

The Eternals are the only beings who have been previously seen in Doctor Who flying replicas of sea going ships through space (see link). The Eternals are beings who generally live outside time and space - in the void (known to them as "The Howling"). They can enter our universe at any given point in time in order to feed off the thoughts and emotions of "Ephemerals", i.e. humans or any alien creatures they come across, in order to fill their empty existence and amuse themselves.

It's a decoration.

The Eternals are flying a replica of the Titanic in space above the earth on Christmas Day. Well that's what i think it is, but Spacephantom mite have a better answer.

because it is a spaceship not the real ship