Human spaceflight is one of the great achievements of the modern age. Not content to master flight in the atmosphere, inventors, engineers, scientists, and visionaries pressed ahead to explore space and developed the technology for human spaceflight. With varying degrees of political leadership and public support, the United States, Soviet Union/Russia, and other nations have made human spaceflight a priority.
Since the first venture into space by Soviet cosmonaut Yuri Gagarin in 1961, more than 500 men and women have flown in space, some staying months at a time. People have circled the Earth in small capsules and huge space shuttles. They have floated in open space, delivered satellites, conducted laboratory experiments, repaired space telescopes, and built a space station. Twenty-four men have flown to the Moon and back (three went twice), and twelve explored its landscape.
After World War II ended, the United States and the Soviet Union began competing for primacy in a global struggle pitting democracy against communism. Tensions between the two superpowers led to such confrontations as the Berlin blockade, the downing of an American U-2 spy plane, and the Cuban Missile Crisis. "Hot" wars erupted in Korea and Vietnam.
Aerial reconnaissance played an important role in this struggle. To supersede its U-2 spy plane, Lockheed developed the top-secret, stealthy SR-71 Blackbird, the world's fastest jet-propelled aircraft, one of which is displayed here. The Cold War ended with the peaceful collapse of the Soviet Union in 1991, and relations between the former adversaries began to warm.
From the beginning of the Space Age, people recognized that Earth-orbiting satellites—able to see and communicate across vast distances—promised unique benefits. In the tense years of the Cold War, such spacecraft (known as applications satellites) evolved down two separate paths: one devoted to national security needs, the other to civilian interests.
Today, hundreds of civilian and military applications satellites ring the Earth, often operating side-by-side in orbit. They provide similar services—communications, photography, remote sensing, weather analysis, and navigation—reaching different but occasionally overlapping communities of users. These satellites have become an integral part of contemporary life. We take for granted daily reports on weather as seen from space and television via satellite, and we have come to expect that satellites will be on alert to enhance national security.