Hello Nature readers, would you like to get this Briefing in your inbox free every day? Sign up here. Researchers have been chasing the concept of a nuclear clock for more than 20 years. Last year, Nature reporter Elizabeth Gibney explained how the imminent discovery could improve on state-of-the-art atomic clocks. () A whole new kind of clock starts ticking Two research teams, one in Europe and one in China, have made the world’s first ‘nuclear’ clocks.