<p>➀ Researchers at JILA and the Technical University of Vienna have discovered a resonant mode in thorium atom nuclei with a low temperature coefficient, which could be a replacement for atomic oscillators in national-level frequency standards.</p><p>➁ The preferred isotope is 229mTh, which has nuclear resonances in the ultraviolet, accessible by lasers.</p><p>➂ The team found a transition with almost cancelled effects, shifting only 62kHz across the measurement range, showing great promise for precision timekeeping.</p>