  We study a circularly moving impurity in an atomic condensate for the
realisation of superradiance phenomena in tabletop experiments. The impurity is
coupled to the density fluctuations of the condensate and, in a quantum field
theory language, it serves as an analog of a detector for the quantum phonon
field. For sufficiently large rotation speeds, the zero-point fluctuations of
the phonon field induce a sizeable excitation rate of the detector even when
the condensate is initially at rest in its ground state. For spatially confined
condensates and harmonic detectors, such a superradiant emission of sound waves
provides a dynamical instability mechanism leading to a new concept of phonon
lasing. Following an analogy with the theory of rotating black holes, our
results suggest a promising avenue to quantum simulate basic interaction
processes involving fast moving detectors in curved space-times.
