The edge of the SOLAR SYSTEM
When most people describe the Solar System, they think only of the eight planets orbiting our Sun. Yet in truth, our neighbourhood goes far beyond that. Outside their orbits lies a vast and invisible expanse of space that astronomers are beginning to shine a light on.
Beyond Neptune lies a ring of icy objects left over from the formation of the Solar System, known as the Kuiper Belt. The region extends between 30 and 50 AU (where 1 AU is the distance between Earth and the Sun). Theorists first proposed its existence after the discovery of Pluto in 1930 led astronomers to wonder if other worlds might be hiding out there. It’s only recently that technology has been able to reveal these icy objects en masse, and now telescopes such as PanSTARRS and the upcoming Vera Rubin Telescope scan the sky every night, looking for the distant specks of Kuiper Belt objects (KBOs) moving across the background stars.
