In the Chinese traditional concept, "the summer and winter solstice", "the spring and autumn equinox" are more valued than other solar terms. In the past, the "autumn equinox" used to be a traditional festival to sacrifice the queen of night. The emperor would hold a ceremony to sacrifice the Luna, and there would also be music and dance performances to reward the gods. In addition, similar to the custom of the spring equinox, people would play " upright egg" on this day. 

The "upright egg" experiment is simple, easy and fun to play: Pick a smooth, well-proportioned fresh egg and gently stand it upright on the table. Although there are many losers, there are also people who "challenge" successfully. This may be because the autumnal equinox belongs to the day of equal day and night in the northern and southern hemispheres. The earth's axis and the orbital plane of the earth's revolution around the sun are just in a state of relative balance of forces, which is conducive to upright egg.

Employee of XMBAG plays upright egg in the autumnal equinox