Final answer:
The astronaut can use the principle of conservation of momentum by expelling gas or propellant in one direction to generate thrust and move away from their initial position in space. This method is commonly used in rockets and spacecraft to maneuver in space.
Step-by-step explanation:
In order to move away from the motionless position in space, the astronaut can use a principle known as conservation of momentum. According to Newton's third law of motion, for every action, there is an equal and opposite reaction. By expelling a mass of gas or propellant in one direction, the astronaut will experience a reaction force in the opposite direction, propelling them away from their initial position.
This principle is used in rockets and spacecraft, where the expulsion of gas or propellant creates thrust, allowing the spacecraft to move in space. By continuously expelling gas or propellant in the opposite direction of their initial position, the astronaut can generate enough thrust to maneuver and return to the space station.
It's important to note that this method works in the vacuum of space, where there is no air resistance. If the astronaut were in an atmosphere, they would also need to account for drag and aerodynamic forces.