Researchers propose redefining Solar System boundaries

Space researchers Jim Green, a former NASA academic, and Ed Belbruno of Princeton University have proposed a new doctrine suggesting the boundaries of the Solar System should be redefined. Rather than a distinct line, they argue the boundary is a complex interaction of gravitational forces, energies, and trajectories.

By accounting for the Milky Way's gravitational field, the researchers suggest the Sun's influence could extend up to 3.8 light-years (approximately 241,000 astronomical units) from the Sun. This scale is comparable to the distance to the nearest stars, such as Proxima Centauri. This contrasts with the current definition of the heliopause at 120 astronomical units or the Oort cloud boundary at roughly 1.5 light-years.

The theory also posits that gravitationally stable Lagrange points (L1 and L2) within the Sun-Milky Way system could function as gravitational ‘portals’ for interstellar objects to enter the Solar System.