Although teachers are prepared in various ways to teach science, depending on the certification standards of their locality and the level at which they plan to teach, few are formally prepared to teach astronomy. In the United States, although astronomy is required for National Science Teacher certification in Earth/Space Science, and recommended for Physical Science, few teachers attempt this certification. Some certification degree programs require or recommend an astronomy course, but it is often at the introductory, non-science major level, or several weeks of astronomy within a science methods course for future elementary schoolteachers. The situation in other countries is no better. In Mexico, essentially no astronomy is taught except at the graduate school level. In South Africa, it is not taught at any teachers' college and only at some of the universities. In Portugal, it is not part of teacher preparation. In many countries, Earth-sun relations appear in the geography curriculum, but the remainder of astronomy is ignored in teacher preparation. In summary. although
astronomy is found in some school curricula, teachers are often not formally prepared to teach it.