Where does the Chinese Yin Yang symbol come from?
When observing the cycle of the Sun, ancient Chinese simply used a pole about
8 feet long, posted at right angles to the ground and recorded positions of the
shadow. Then they found the length of a year is around 365.25 days. They even
divided the year's cycle into 24 Segments,
including the Vernal Equinox, Autumnal Equinox, Summer Solstice and Winter
Solstice, using the sunrise and Dipper positions.
They used six concentric circles, marked the 24-Segment points, divided the
circles into 24 sectors and recorded the length of shadow every day. The
shortest shadow is found on the day of Summer Solstice. The longest shadow is
found on the day of Winter Solstice. After connectingeach lines and dimming Yin Part from Summer Solstice to Winter Solstice, the
Sun chart looks like below. The ecliptic angle 23 26' 19'' of the Earth can be
seen in this chart.
No comments:
Post a Comment