All organisms from fruit flies to humans share the same mechanism for controlling the day and night rhythms also called the circadian rhythms. This mechanism is considered fundamental to all advanced life forms, and it has a surprising feature. It binds us genetically to live on earth. Michael Rosbash received the Nobel Prize in Medicine in 2017 for the discovery of the circadian rhythms together with Jeffrey Hall and Michael Young. He is a professor and Howard Hughes Medical Institute investigator at Brandeis University. In 2019 he was invited by The Royal Danish Academy of Sciences and Letters to give the nineteenth Royal Academy Nobel Laureate Lecture in Copenhagen and was interviewed by science journalist Jens Degett. Photo credit: Chris Heller for Science Stories.