The best way to describe the proposed orbit is to consider the plane of the elliptical path cutting through a celestial sphere globe at Sirius, the “belly” of Hydra, and the “back” of Serpens (fig. B1).

There is but one way in which this flat plane cuts those three points. The path is in the shape of a highly elongated ellipse (two relatively sharp curves at two opposing points), one of those points is toward Sirius and deepest in space beyond Pluto/aphelion, and the other point is on the other side of the Sun (opposite Sirius) at closest approach to the Sun/perihelion.