Who invents the rockets?

Answer 1

Alchemical research in China between the 9th and 13th centuries yielded most early discoveries in gunpowder and rocketry. Reliable documentation of rocket use first emerges in the 13th century, from Chinese accounts and subsequent European accounts of Mongol use.

short answer - China

Answer 2

One of the first devices to qualify as a rocket was a wooden bird. The writings of Aulus Gellius tell a story of a Greek named Archytas. Around the year 400 BC he stunned the townspeople by flying a pigeon made of wood. Escaping steam propelled the pigeon suspended on wires. The bird is an example of Newton's third law of motion- every action has an equal and opposite reaction.

About one hundred years later, a Greek named Hero invented a similar rocket-like device called an aeolian. It used steam to propel it. Hero put a sphere on top of a water kettle with two L-shaped tubes on opposite sides of the sphere. The tubes let gas escape. A fire below the kettle turned the water into steam, the steam gave the sphere a thrust, and it rotated the sphere.

Dr. Robert Hutchings Goddard constructed and successfully tested the first rocket using liquid fuel. In 1914, Goddard received two U.S. patents. One was for a rocket using liquid fuel. The other was for a two or three stage rocket using solid fuel.

See the related question for more information on Space Rockets.