She cautiously kept one hand on the rail, to steady herself in the micro-g environment.

A "stationary" micro-g environment would require travelling far enough into deep space so as to reduce the effect of gravity by attenuation to almost zero.

A temporary micro-g environment is applied for training of astronauts, for some experiments, for filming movies, and for fun.

What remains is a micro-g environment moving in free fall, i.e. there are no forces other than gravity acting on the people or objects in this environment.

A micro-g environment for an indefinite time, while also possible in a spaceship going to infinity in a parabolic or hyperbolic orbit, is most practical in an Earth orbit.

The term micro-g environment (also g, often referred to by the term microgravity) is more or less a synonym of weightlessness and zero-G, but indicates that g-forces are not quite zero, just very small.

A temporary micro-g environment exists in a drop tube (in a tower or shaft), a sub-orbital spaceflight, e.g. with a sounding rocket, and in an airplane such as used by NASA's Reduced Gravity Research Program, aka the Vomit Comet, and by the Zero Gravity Corporation.