The same is true when they throw objects for the camera. There is no interfering force to cause this situation to change. Have you ever noticed that their tools float? They can just place them in space and they stay in one place. You can see good examples of this idea when you see video footage of astronauts. If you're going in a specific direction, unless something happens to you, you will always go in that direction.
If nothing is happening to you, and nothing does happen, you will never go anywhere. Motion (or lack of motion) cannot change without an unbalanced force acting. The first law says that an object at rest tends to stay at rest, and an object in motion tends to stay in motion, with the same direction and speed. The ideas have been tested and verified so many times over the years, that scientists now call them Newton's Three Laws of Motion.
During his work, he came up with the three basic ideas that are applied to the physics of most motion (NOT modern physics). He worked on developing calculus and physics at the same time.
A little bit stuffy, bad hair, but quite an intelligent guy. There was this fellow in England named Sir Isaac Newton.
