Earliest Recorded Total Eclipse of the Sun

Earliest Recorded Total Eclipse of the Sun

The earliest recorded total eclipse of the Sun probably occurred on October 22, 2134 b.c., and was chronicled in China, in the ancient document Shu Ching, which says, “The Sun and Moon did not meet harmoniously.” A solar eclipse takes place when the Moon's monthly orbit around Earth brings it directly between Earth and the Sun, so that the Moon's shadow tracks a path across the face of Earth. The path of total eclipse can be up to 167 miles wide and the path of partial eclipse along its sides up to 3,000 miles wide, but because they are both usually much narrower, comparatively few people witness the event. Those who are within the zone of shadow see the Sun grow thin and finally vanish, as an untimely night descends; then, less than 10 minutes later, the Sun will begin to reappear as the shadow moves on. This spectacle has inspired awe and terror since earliest times.

Not every monthly lunar orbit brings the Moon directly between Earth and the Sun. The Moon's orbital plane around the Earth is at a slight tilt compared to the Earth's orbital plane around the Sun, so that direct alignment takes place only once every 6,585.3 days, or just over 18 years. This period of time is called the Saros. The predictability of the Saros was known by the ancient Babylonians and Assyrians, but apparently not by Hsi and Ho, two of the imperial astronomers of ancient China, who failed to predict the eclipse of October 22, 2134 b.c., and were consequently beheaded. At the time, the common people of China believed that eclipses were caused by an invisible dragon attacking the Sun. To scare the dragon away, they would shout and bang on drums, and shoot arrows into the sky (since eclipses do not last very long, these tactics always seemed to work). When Hsi and Ho failed to alert the emperor to an upcoming eclipse, so that he could assemble his drummers and archers in advance and show himself a beneficent ruler, he was highly displeased and had them put to death.