I am reading a book on ancient astronomy and it claims that around the year 1500 the position of the sun, at the time of the spring equinox, was on the tail end of the second fish in the constellation of Pisces. Now I understand this might be more guess work than anything else but I am wondering if this claim could be even remotely true. I don't even know where to begin in calculating this. Any help is appreciated.
The position of the sun, relative to the stars, at the time of the equinox changes slowly and predictably. This means that we know to a high degree of precision exactly where the sun was at the time of the equinox in 1500.
It is pretty easy to calculate The position of the sun at the time of the equinox changes by about 1 degree every 71.3 years. The sun is currently in pisces at the time of the Equinox. 520 years ago it would have been 7.3 degrees closer to Aries.
Dbachmann / CC BY-SA (http://creativecommons.org/licenses/by-sa/3.0/)