Scientists in Denver have discovered that the Universe has a floor. Observations of an exploding star in the Andromeda galaxy revealed that the blast knocked one of the planets off the little stick that it goes round on. It rapidly dropped out of sight, but then astronomers, expecting that they would never see it again, were considerably surprised to see it bounce back up into view.
From more recent observations of bouncing planets, boffins have been able to infer more details of the Universe's mysterious floor, including strong indications that it's covered in lino and probably hasn't seen a broom for a good few millennia.
Exciting though these findings are, there is still no firm indication on whether the Universe has a ceiling, although there is consensus that someone has left a window open, as there certainly seems to be a draught coming from somewhere.
Planets are on sticks, right?