This was a somewhat rare event – a full moon occurring not just at perigee, but at the closest perigee of the year. But many people got the impression that this was an exceedingly unusual event, and rushed to see and capture images of this supposedly ultra-rare moon. Depending on how closely you require the full moon to occur to perigee in order to call it a supermoon, though, these events happen at least roughly once a year, and often more frequently.