High-angular-resolution studies of symbiotic novae

Novae stars have fascinated observers around the world for centuries.They are eruptive close binary stellar systems consisting of a white dwarf and a secondary stellar component, which in rare cases is a red giant.Such systems are called symbiotic novae.Since the nova phenomenon is unexpected in most cases, there is a lack of observations and understanding, especially of the very early phases of their eruptions.To resolve and understand these early epochs, very fast and exceptionally high-angular-resolution methods of observations are needed.Symbiotic novae are the right systems for studies in the infrared, thus the optical interferometry is the ideal solution in this case.We discuss three of them, namely RS Oph, V3890 Sgr, and T CrB.