Extremely toned down story version: Ancient gateway that leads to other worlds for faster transportation, constructed by beings known as the Ancients. You walk through it like you would a door. I'd rather not waste a page trying to explain the plot.
considering its name
I believe it is a 40th century teleportation device that splits your body in to numerous atoms and splitting them apart until your atoms become some of the stars and the star's gravity slingshots your particles through the infinite universe until you reach a certain point in time where a separate stargate is created. your atoms continue to circle around the star directly above the stargate until they form a body, an unconscious body, which is then dropped down to the stargate. You awake thinking you were teleported.
But since there are no stars in the Bedroom Map, I think this is a portal (not handheld)
Way to pull that out of your ass.