Working as a zookeeper requires you to be passionate about animals and wildlife conservation. You often spend more time with the animals than other zoo employees, getting to know their habits and personalities. This helps you determine when the animals are healthy or whether they need veterinary care, a vital role of primary caregivers.
So on average the number of days between two similar phases (e.g. between one full moon and the next full moon) is about 29.531 days. This period is referred to as a lunation, lunar month, or synodic month.
Blue Moons are not as rare as the old saying once in a blue moon implies; they happen about once every 2.7 years, because the number of days in a lunation (new moon to new moon) is a bit less than the usual calendar month â 29.53 days as opposed to 31 or 30 days (except for February, which has 28 days, so a blue moon cannot occur).