SF - Mooncake/Mid-Autumn Fest. Mama beaver Aubrey Woodbrook enjoying tea w/ mooncake. The Mid-Autumn Festival (Chinese: 中秋節; Japanese: 月見), also known as Mooncake Festival, is celebrated in many East Asian communities. In China, it's a reunion time for families, just like Thanksgiving, while in Vietnam, it's more like a children's day. It is the second-most important Chinese holiday after Chinese New Year with a history dating back 3,000 years, when China's emperors worshipped the moon for bountiful harvests. The celebration is called Tsukimi (moon-viewing) in Japan. It traditionally falls on the 15th day of the eighth month in the Chinese lunar calendar, which is in September or early October in the Gregorian calendar.