When people have no forces to support their weight, such as astronauts in space, they can feel the sensation of .

The sensation they feel is called "weightlessness". This happens because there is no force of gravity acting upon their body. Here are the steps that explain this:

1. On Earth, our weight is determined by the force of gravity pulling us down towards the ground. This force is what gives us our sense of weight and keeps us grounded.

2. In space, the force of gravity is much weaker than it is on Earth. This is because gravity decreases with distance, and in space, you are much further away from the Earth's center of mass.

3. Because the force of gravity is so weak in space, it does not pull us down with the same force that it does on Earth. This means that we do not feel our weight in the same way.

4. This lack of a downward force, or weight, is what gives astronauts the sensation of weightlessness. They are still subject to gravity (in fact, they are in a constant state of free fall towards the Earth), but they do not feel it because there is no force pushing up against them to give them a sense of weight.

5. This sensation of weightlessness can be disorienting, as our bodies are used to the constant pull of gravity. However, astronauts train for this in order to be able to function effectively in space.