The symbiotic system AG Dra: an unexpected photometric period

A photometric period of about 380 days is found in 6810 visual magnitude estimates of AG Dra. This is unexpected, since the orbital period of the system is about 552 days. The period is confirmed by Hipparcos photometry. The new periodicity provides an additional constraint on physical models for AG Dra. Detailed observations before the end of the present outburst phase may help to clarify its nature.