Ultracold atoms have proved to be a versatile system with applications ranging from quantum simulation to foundational physics experiments. Using this system, we address an apparently simple question: how long does it take for a particle to tunnel through a potential? This question has attracted debate since the beginning of quantum mechanics. In this talk, I will discuss the progress towards this measurement, and the current challenges. Also, I will present our latest result in atom thermometry, where we are able to characterize atomic momentum distributions in the picoKelvin regime.