Kusufi na shekara wani nau'in kusufin rana ne da ke faruwa a lokacin da wata ya yi nisa da duniya ba zai iya rufe faifan rana gaba daya ba. A sakamakon haka, a lokacin husufin rana, wata ya zama ƙasa da rana, yana barin "zoben wuta" a gefen faifan hasken rana. Wannan yana haifar da tasirin gani mai ban sha'awa wanda ake iya gani daga wasu sassan duniya yayin kusufin.
