Multi-spacecraft study of foreshock cavitons upstream of the quasi-parallel bow shock

► A new type of structures in the Earth's foreshock has been studied - the foreshock cavitons. ► Properties of these structures (form, size, velocity, etc.) are calculated. ► Observational differences between foreshock cavitons and foreshock cavities are discussed. ► New insights on the dynamics of the Earth's foreshock are obtained.