Are You Really Weightless in Orbit?

Gravity acts on you even while you are in orbit, and therefore you still have weight. But what is missing is the familiar sensation of weight.
Without air resistance, all objects fall at the same rate. Because you and your spacecraft are falling at the same rate, there is no force between you and it to provide a sensation of weight. You drift about as though gravity has lost its grip.
Feelings you take for granted and hardly notice on Earth-- the downward pull on your arms and on your internal organs, the pressure against your feet as you stand or walk, your sense of up and down--are suddenly absent. You feel "weightless."

Astronauts in orbit seem "weightless" because of how they are moving, not because they are in space. If you could stand at the top of a ladder that extended all the way into space, you would not feel "weightless," since you would not be falling.

Courtesy of NASA

Surface tension shapes a free-falling liquid into a sphere. Here, an astronaut aboard the Space Shuttle prepares to drink an orb of orange juice that is floating about the cabin.

---

(Rev. 09/19/96)