For decades, planetariums have been created to serve the cause of astronomical enlightenment – to offer people knowledge and understanding and a sense of place in a universe far bigger than themselves. It is an important role and one that we in planetariums continue to play – changing, we hope, as times, technology, educational philosophies, and our view of the universe change.

The first projection planetarium was demonstrated by the Zeiss Optical Company at the Deutsches Museum in Munich, Germany in 1923. By 1970, the height of the Apollo moon program, there were an estimated 700 to 800 planetariums in the world, half of them less than six years old. Today, 26 years later, that number has more than doubled to a little over 2,000.

The world organization of the planetarium profession is the International Planetarium Society with over 600 members in more than 30 countries. Based on figures compiled in the 1995 IPS Directory, we find that slightly more than half of the world's planetariums are located in North America, with large numbers also in Asia and Europe, but relatively few in other parts of the world. If we consider distribution by country, we find that half are in the United States, more than 300 are in Japan, and Germany ranks third with nearly 100. Nineteen countries have ten or more planetariums.

Some 33 percent of the worlds’ planetariums are located in primary or secondary schools; 17 percent are at colleges and universities; 15 percent are part of museums and science centers; 7 percent are associated with observatories or other institutions.