Why is Aries the first house of the constellation?

"In the eyes of the Babylonians, the sun is Apollo, and its resting place must be a magnificent palace. So they call the 1 section of the ecliptic "1 palace", but this sentence omits some important information, that is, the time of their observation. The answer to this sentence is vernal equinox. At this time, the longitude of the sun is 0 degrees, and the sun just runs near Aries, so 6548.

Each constellation lasts about 30 days. If you use professional astrology software, you will find that there are actually several hours of discrepancy.