Ever since Isaac Newton famously talked about gravity, its dominance as a force in our solar system has been well known. It's responsible for the orbits of the planets and their satellites, but there are other forces that have shaped our planetary neighborhood.

A new paper discusses how recoiling ice from comets can push them around and how the radiation pressure from the sun drives material outward. There are also relativistic effects that can cause particles to spiral inward toward the sun.