Astrobiology is, on a profound level, about whether life exists outside of the planet Earth. The question of existence of life elsewhere in the universe has been of interest to many societies throughout history. Recently, the research area of astrobiology has grown at a fast rate, mainly due to the development of observational methods, and the media is frequently reporting on new research findings. International surveys show that astrobiology questions are among those that interest young people the most. The popularity of astrobiology and the way it captures much science content makes it an interesting area for science teaching. However, there is very little research directly focused upon students' views in astrobiology. The study reported in this paper draws from the answers of 186 Swedish lower secondary students (16 years old) to a questionnaire, with closed and open-ended questions regarding their views of issues in astrobiology. The study was guided by the worldview theory (Cobern 1991; Cobern, "Science Education" 80(5):579-610, 1996; Cobern, "Science and Education" 9:219-246, 2000). The results show that even though basic reasoning in astrobiology is known by a majority of the students, there is a considerable number of students, for whom this is not the case. Furthermore, it was found that for all questions, there are students answering in different ways when asked to describe their own view and the view they associate with science researchers. The implications of the study for further research and for the teaching of astrobiology in science class are discussed.