Tsukimi (月見) is a very low key festival. It’s celebrated on the 15^th of the eight month on the lunar calendar. It’s said that the 15^th of the eighth month is when the moon is the brightest and fullest.  People go outside to see the moon, and as you can see, it’s very visible in the dark :

A common tradition is to make white, round, sweet dumplings called tsukimi dango (月見団子); which are made in the shape of a round moon.

If you’re wondering what those round, brown things were in the video, those were chestnuts. The 15^th of the eighth month on the lunar calendar is a day of large harvests. The chestnuts symbolize the plentiful harvest.