The term SOS Lights is a reference to the international distress signal, which is used to indicate a life-threatening emergency. The signal consists of three dots, followed by three dashes, and then three more dots. In this crossword, the solution for SOS Lights is 'FLARES, ' which are a type of pyrotechnic device used to signal distress. FLARES are typically used in maritime emergencies, and can be seen from a great distance.