All novae are binary stars, with a "donor" star orbiting a white dwarf. The two stars are so close to each other that matter is transferred from the donor to the white dwarf. Observations by the satellite TESS detected a variation in the light curve of V407 Lupi indicating an orbital period for the binary system of 3.513 days; it was previously thought to be 3.573 hours, but this has since been disproven. A second periodicity in the light curve was also detected by the Chandra X-ray Observatory and has a period of , which appears to be the rotation period of the white dwarf. The very rapid decline from peak brightness indicates that the mass of the white dwarf is ≥ 1.25 , not far below the Chandrasekhar limit for white dwarf masses. The system is probably an intermediate polar nova.
