Does the planet Jupiter have a protective effect on our Earth?

Answer

Indeed, the planet Jupiter influences the orbits of small celestial bodies that come close to it. In principle, this would indeed allow Jupiter to deflect an object on its way to Earth on a collision course and thwart the catastrophe; but it is equally likely that the deflection of an object that would not initially strike Earth will just send the body toward Earth. In this sense, Jupiter’s role is neutral: good and evil balance each other.

Yet it is rightly said that thanks to Jupiter, the danger of impacts is less than if Jupiter had not been there. That’s because Jupiter’s presence has influenced the orbits of many minor planets since the early stages of the solar system. Jupiter’s perturbations cause its orbits to become more diverse, increasing the likelihood of an object colliding with another (or the sun) or even being catapulted to the outer orbits of the solar system. But once they’re gone, they’re gone. Thanks to Jupiter, there have been more events in the past, so things have calmed down a bit today.

It is likely that Jupiter has been kind to us in another way as well. When the Earth was formed, it was probably so hot that most of the water was gone. The fact that there is now enough water to support oceans – and life – may be due to a later episode of cometary incursions on Earth, in which Jupiter would have played a determining role.