Although Cetus is not generally considered part of the zodiac, the ecliptic passes close to its constellation boundary, and thus the planets may be seen in Cetus for brief periods of time.

There are examples of stars bearing Flamsteed designations for constellations in which they do not lie, just as there are for Bayer designations, because of the compromises that had to be made when the modern constellation boundaries were drawn up.

In this 5th edition the Milky Way was included for the first time, and he incorporated the official constellation boundaries that had been laid down by the International Astronomical Union in 1930.

For the purpose of determining the constellations in contact with the ecliptic, the constellation boundaries as defined by the International Astronomical Union in 1930 are used.

Needless to say, the IAU defined the constellation boundaries without consideration of astrological purposes.

The constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 26 sides.

However, when the constellation boundaries were officially established by the International Astronomical Union in 1930, this star was located within Ursa Major.

As it is located at a declination of 50 to 70 degrees, the whole constellation is only visible south of latitude 30 N. The official constellation boundaries, as set by Eugène Delporte in 1930, are defined by a polygon of 14 segments.

The official constellation boundaries were defined in 1930 using B1875.0.

Berg breaks from historical tradition to combine sidereal astrology with the IAU's official constellation boundaries defined in 1930, creating a 13-sign system.