At a distance of 8.6 light years, the Sirius system is one of our solar system's nearest neighbors. Sirius A is about twice as massive as the sun and about twenty-five times as bright. The idea that Sirius could be a companion star to the sun was first proposed by the mathematician and Egyptologist R.A. Schwaller de Lubicz, who made his deductions from studying the ancient Egyptian calendars that used the helical rising of Sirius as their New Year date. In his book Sacred Science, he observed, “It is remarkable that owing to the precession of the equinoxes, on the one hand, and the movement of Sirius on the other, the position of the sun with respect to Sirius is displaced in the same direction, almost exactly to the same extent.”

Schwaller de Lubicz inspired the father and son research team of Karl-Heinz Homann and Uwe Homann to form the Sirius Research Group, one of the modern pioneers of binary star theory. They believe the sun's binary companion is the dog star, and have compiled a great deal of evidence that supports a close connection between our sun and Sirius.

Conventional astronomical calculations suggest the chance of Sirius being a companion star is remote. Nonetheless, our sun and Sirius are moving toward each other, demonstrated by the distinct blue cast to the appearance of Sirius. This shows a companion relationship is at least possible. One other possibility is that a more complex arrangement exists where the sun and Sirius are both binary systems, yet they also revolve around each other.