Human Space Flight
The Apollo program was a NASA mission to land humans on the Moon from 1969 to 1972. Six of the missions (Apollo 11, 12, 14, 15, 16, and 17) were successful in landing astronauts on the Moon. There were also many unmanned Moon landings. The Apollo missions followed NASA's Mercury and Gemini missions.
The International Space Station (ISS) is an artificial satellite in a low Earth orbit, roughly 400 km above the Earth's surface. It was launched in 1998 from the Kennedy Space Center at NASA. The ISS is a collaboration between space agencies around the world, and is divided into two sections: the Russian Orbital Segment and the United States Orbital Segment.