This paper presents the results of the first survey conducted in Belgium about the interest in and knowledge of astronomy. Two samples were studied, the public at large (667 questionnaires) and students (2589 questionnaires), but the results are generally similar in both samples. We evaluated people's interest, main information source and attitudes towards astronomy, as well as their supposed and actual knowledge of the subject. The main conclusion is that, despite poor self-confidence, people do know the basic astronomical concepts. However, that knowledge is not deeply rooted, as reasoning questions show widespread misconceptions and/or misunderstandings.