Did You Know? Did you know that the rainy season, which is also called vassa, actually starts the day after the full moon, rather than on the full moon day itself? Not many people know this, but why is that? It’s because the full moon day is actually the last day of the lunar month. The new lunar month begins on the day just after the full moon. Although the public ceremonies for the lay people are held on the full moon day, that’s just for the laity, which is why most people don’t realize how the monastic calendar works.