NASA was founded in 1959 by an act of Congress. President Eisenhower founded NASA as a civilian space agency as a rebuttal to the tendency toward Cold War tensions, and the militarization of space. So the United States has always had a civilian space agency dictating that its mission be towards exploration and scientific knowledge rather than militarization. However, NASA existed in a situation of the Cold War, and the early part of the space activity was driven by geopolitical considerations and our rivalry with the Soviet Union. At the core of what NASA does in space is the launch capability. There has no rocket until recently that they succeeded the enormous capabilities of the Saturn five rocket that took the astronauts to the moon, and led to the Apollo program. To launch astronauts and payloads larger than a couple of tones, a new heavy lift capability is required. The United States has been struggling to fund this activity through NASA. As a result of NASA's funding and technical difficulties, space exploration has been on a relatively slow track over the last few decades, and currently it's not possible to put astronauts into space. We have to rely on the Russians and the Soyuz spacecraft. Within NASA, the budget is of course divided into several categories. There's exploration, which involves human exploration, and unmanned or robotic spacecraft traveling through the solar system. There's also research on Launch Capabilities, Rocketry and propulsion. NASA has a growing part of its research enterprise devoted to looking at the Earth and understanding the ways that the Earth is changing, and managing the Earth's resources, but uncertainties in funding have caused the timeline of many favorite projects among scientists to be extended, and some projects have even been canceled. Many of the most ambitious projects in astronomy and space science and Planetary Exploration now have to be collaborative. With price tags exceeding a billion dollars, it makes sense to collaborate. NASA's counterpart, the European Space Agency has its own substantial capabilities. For example, ISA, is a partner in the Hubble Space Telescope and will be a partner in the James Webb Space Telescope. ISA also has its own planetary missions and astronomy missions. This cooperation with a little bit of rivalry is a healthy situation, and has allowed some missions to happen which would not have happened just depending on NASA. There's also collaboration between the Americans, the Europeans and the Japanese space agency, not so much with the Chinese who have a growing space activity. The growing complexity and price tags especially of planetary science and astronomy missions, has led to the problem of new starts. NASA's budget is essentially static and has been so for a decade, which means that the number of new missions or new starts is declining and has been for ten or 15 years. As the budgets go up and emission takes roughly a decade to plan and execute, this squeeze is limiting the amount of science that NASA can do. If we look at the history of NASA's budget over its entire span, we can see that the sixties when the Apollo missions were launched, was an anomaly. NASA's budget ramped up rapidly by a factor of ten to an almost unsustainable level amounting to five percent of the budget the federal budget at that time. Since then it declined. The last three Apollo missions were actually cancel, and NASA's budget in real terms has been pretty static for the last 15 years. As a fraction of the federal budget, NASA's budget has migrated down to one percent and even less. It is a relatively small amount of federal money corresponding to about one taxpayer dollar per year. Meanwhile, opinion polls show that public support for NASA is relatively strong. The general public like the idea of space travel and space exploration, and the discoveries of astronomy that result from things like the Hubble Space Telescope. However, they're not necessarily willing to pay it. Of course, it turns out that the public when asked what fraction of the federal budget NASA occupies, almost always overestimate this by a significant factor. Since its inception, NASA has always been a civilian space agency, and militarization of space is something that all countries tried to guard against. NASA's current budget is about $18.5 billion, which sounds like a lot of money, but it's actually insufficient for NASA to execute its best ideas giving the increasing cost and complexity of space missions. Since its peak during the Apollo era, NASA's proportion of the federal budget has declined strongly, and more recently slowly from about one percent down to about 0.5% of the federal budget. Despite this, public support of the space enterprise remains strong.