Apollo's purpose was way bigger than just sending humans into space and having them land safely. Its purpose was:
*Establishing the technology to meet other national interests in space.
*Achieving preeminence in space for the United States.
*Carrying out a program of scientific exploration of the moon.
*Developing man's capability to work in the lunar environment.
*And the main one was to send a man to the moon and back.
The Gemini Project went on for a duration of 5 years(1961-1966). This project was the second human spaceflight made by the United States. the spacecraft carried two astronauts. Gemini's purpose was to simply send an astronaut into space and bring them back to earth safely.
This is Gemini^-^
Space Stations are basically huge spacecraft's that orbit around the earths atmosphere they also serve as a home where astronauts can live. Scientists also use this as a lab to study space.
Sputnik was the first satellite that was successfully placed in earths orbit, made by the Soviets. The word "Sputnik" means "Satellite" and translated as "Fellow Traveler". On January 4th, 1958, it burned and came back to earth.
This is Sputnik^^^
This Is Apollo^^.^^
This Is The International Space Station^^^^^^^^^^^^