Where does a helium balloon go in zero gravity?

The reason a helium balloon rises in the earth's atmosphere is because helium has lower density than air. To put it another way: a volume of air weighs more than the same volume of helium. The balloon rises because all the heavier air is pulled down below it. See Buoyancy for a more detailed explanation. read more

Helium balloon rises in the earths atmosphere because the buoyant force provided by the atmosphere is more than the force due to gravity. In outer space the effect of gravity can be taken to be zero. Assume there is no atmosphere (vacuum) Since there are no forces acting on the balloon it will remain stationary. read more

Helium balloons are pulled by gravity, as are all objects with mass. The reason they don't fall is that there is another force acting on them, a buoyant force from air pressure that is equal to the weight of the air displaced by the balloon. read more