Space exploration remains dynamic as developments have been ongoing over the years with several countries actively making their contribution to space exploration; and have continued to show interest in the long-term focus on space colonization. Three prominent countries at the fore of space exploration and showing interest in colonization include the United States, China, and Russia.
The United States, NASA (National Aeronautics and Space Administration), has played a lead role in space exploration since when it was established in 1958. They have a rich history of crewed space missions, which included the Apollo moon landings. In recent years, NASA has paid more attention to projects some of which are: