二十四节气 (Èrshísì Jiéqì), the 24 solar terms, are 24 festival days in Chinese calendar year. Each marks 15 degrees of the Earth’s travel around the Sun, and they fall at the beginnings of each season, the equinoxes and the solstices (winter solstice coming up this week!).
Many of the festivals are named after the natural phenomena that happen at the time: For example, the mid-March festival is called “The Awakening of the Insects”, and late April is when you get both “Grain and Rain”.
Though only some of them are celebrated, all of them are learned by Chinese schoolchildren through mnemonics such as the “Song of the Solar Terms”. Some are also celebrated in simple ways: For example, for the winter solstice, Northerners will eat dumplings while Southerners will eat 汤圆, tāngyuán, little sweet chewy soup balls that you should definitely try.
The days start getting longer after this week - unless you're Australian or something...
Picture by Luke Price