The year 2024 was a breakthrough year towards the development of a nuclear optical clock, with three experiments reporting success in the laser spectroscopy of the lowest nuclear excited state of 229-Th. The highest accuracy was achieved at JILA via direct frequency comb spectroscopy of this, previously elusive, nuclear state. This success is the result of several decades of effort to precisely determine the transition energy and a first step towards nuclear precision spectroscopy and the development of a nuclear frequency standard of extremely high accuracy.
In this talk I will provide an overview over the history of 229-Th that has culminated in this success. Further, I will discuss the remaining efforts and challenges. Finally, I will introduce the investigations underway within the framework of the BMFTR-funded project “NuQuant”.