The law of motion that explains how rockets are launched into space is Newton's Third Law of Motion:

For every action, there is an equal and opposite reaction.

Here's how it works:

* Action: The rocket engine burns fuel, expelling hot gas out of the nozzle at high speed.

* Reaction: The expelled gas pushes back on the rocket, propelling it upwards.

This principle is crucial to rocket propulsion. The rocket expels a large mass of gas at a high velocity, generating a significant force in the opposite direction, allowing the rocket to overcome Earth's gravity and escape into space.

It's important to note that while Newton's Third Law is fundamental, other laws of motion also play a role in rocket launch:

* Newton's First Law: The rocket remains at rest until the force of the engine overcomes its inertia.

* Newton's Second Law: The acceleration of the rocket is proportional to the force applied by the engine and inversely proportional to its mass.

So, while Newton's Third Law is the key principle explaining how rockets launch, a combination of all three laws of motion are at play.