The distinction in how Jupiter impacts completely different teams of small our bodies has to do with Jupiter’s position in every sort of object’s actions. Oort Cloud comets have a tendency to remain within the far reaches of the Photo voltaic System, however typically they are often nudged into orbits that take them nearer to the Solar. This will occur due to the shut passage of a star or big interstellar molecular cloud close to the Photo voltaic System, or due to the gravitational forces, referred to as disk tides, exerted by the mass of the galaxy as an entire. The forces are from very distant sources, however are mighty sufficient to have an effect on the motion of small icy our bodies.
When this does occur, Jupiter is effectively positioned to be our defender. It’d suck a comet proper into its personal physique, or may pull it in simply sufficient to slingshot it out once more, even proper out of the Photo voltaic System.
With asteroids and short-period comets, Jupiter’s affect is probably going what causes a small physique to go away its present orbit and head off in an odd new course. Simulations recommend that without a planet like Jupiter in the Solar System, there could be much less gravitational disruption of asteroids’ and comets’ orbits, probably inflicting fewer impacts with Earth and different inside planets.
Additional work is required to raised perceive Jupiter’s actual affect on impression charges on Earth. For now, the fuel big’s fame as protector of the inside Photo voltaic System isn’t clear-cut.
Our greatest protection? Ourselves.
Jupiter might or is probably not our ally in planetary protection, however finally, it’s our accountability to defend ourselves. That’s why The Planetary Society is dedicated to advancing efforts to seek out, monitor, characterize, and deflect probably harmful asteroids and comets.