Newton’s Laws of Motion in Space!

Newton’s First Law of Motion: An object at rest tends to stay at rest, and an object in motion tends to stay in motion unless acted on by an unbalanced force.

The forces acting on this rocket are balanced; therefore this rocket will remain at rest.

Once an unbalanced force is applied to the rocket, the rocket accelerates upwards.

Gravity causes both the International Space Station and astronaut Victor Glover to orbit the Earth. Astronaut Victor Glover will continue floating through the ISS unless an unbalanced force, like grabbing a handrail or bumping into an object, is applied to him.

Newton’s Second Law of Motion: The total force is equal to mass times acceleration (F = m x a). Mass and acceleration are inversely proportional, meaning that as mass increases, acceleration decreases and as mass decreases, acceleration increases.

If a large force is applied to a small mass, it will have a large acceleration. If the same force is applied to a larger mass, it will have a smaller acceleration than the smaller mass.

The Falcon 9 Heavy rocket on the other hand has a mass of 1,420,788 kilograms and produces a force of 20,820 kilonewtons during liftoff. This rocket requires a larger force to accelerate during liftoff because it has a larger mass.

Newton’s Third Law of Motion: For every action, there is an equal and opposite reaction. This means that forces exist in pairs.

A force pair identifies two interacting objects and describes the direction of the force acting on each object. The ARED uses Newton’s Third Law to make it possible for astronauts to exercise in the weightless environment of the International Space Station.

As astronaut Suni Williams applies a force onto the ARED platform, the ARED platform applies an equivalent force back onto her in the opposite direction.

To watch Newton’s Laws of Motion in action aboard the International Space Station, visit www.nasa.gov/stemonstation