i'm going to remove the notion that the ecliptic didn't cross ophiuchus before since it is clearly contradicted by this ophiuchus the story seems to be that before the area that now only belongs to ophiuchus belonged to two or more constellations in order to formalize it astronomers had to choose one if they choose one of the astrological signs they would avoid angering astrologers if they choose ophiuchus one of the most important documents in astronomy kepler's de stella nova in pede serpentarii on the new star in ophiuchus's foot would still be meaningful to future astronomers they would also honor kepler and ptolemy who first described the constellation over years earlier it comes as no surprise that they acted as they did feb utc