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How did the legend of western constellations come from, under what background and what is its significance?

The origin of constellations

In ancient times, people had to know the seasonal changes in detail for animal husbandry and agriculture. They noticed that the arrangement of stars in the sky is different in different seasons. In order to facilitate the memory and dissemination of this knowledge, they use their imagination to connect the chaotic stars in the sky, which is the origin of the constellation.

Western constellation

Western constellations originated in ancient Greece, and the earliest mention of constellations was in a poem Phaenomena written by the Greek poet Aratus in 270 BC. As can be seen from this poem, the word constellation was known to mankind before Aratus.

The constellation mentioned by Aratus has no stars at all near the south celestial pole. This may be because these stars are all below the horizon of the region where the constellation name is located. From these unmeasurable horizons, we can infer that the people who named the constellations probably lived at about 36 north latitude, that is, south of Greece and north of Egypt, where Babylon and Sumer were located.

Due to the precession of the earth's rotation, the north and south poles of the earth will deviate periodically with time. According to calculations, this unexplored celestial sphere was just above the south celestial pole in 2000 BC, which was also the time when ancient Babylonians and Sumerians lived.

Based on this, we have great reasons to believe that Greek constellations originated in ancient Babylon and Sumer. The knowledge about constellations later spread to Egypt and was known by some Greek scholars who lived there at that time.

In A.D. 150, the Greek scientist Ptolemy compiled an astronomical book named "Astronomical Table", which summarized the astronomical knowledge of the Greeks at that time, including the names of 48 constellations and 1022 stars, and the estimation of their luminosity.