The Sol Ring, simply known as the Ring, is a gigantic alien structure located about two Astronomical Units (AU) outside the orbit of Uranus. It is shaped like a ring or torus with an inner diameter of approximately 1000 kilometers, with a series of twisting ridges that spiral around its body. It is the product of a complex of self-assembling structures that emerged from Venus after the protomolecule seeded the planet via Eros.
The structure is apparently an artificially sustained two-way Einstein-Rosen bridge, or wormhole, leading to an unknown location known as "the slow zone". Any object that passes through the Ring instantly appears on the other side in the Slow Zone. Sensor data, including visible light, also travels instantaneously and merely treats the Ring as a window with no physical distance between the two sides; however, there is some distortion that occurs when light or other electromagnetic radiation passes through the Ring.
The Ring near Uranus is part of an ancient Ring network created by an unknown alien race approximately 2 billion years ago. Rings were seeded by self-assembling materials which activated when planets of Earth-like characteristics were detected. Once these rings were assembled, other planets could be accessed through the Ring network.